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Mike

Late to the Electric Party

April 1st, 2016 Tesla unveiled their much anticipated Model 3. Thousands put down deposits, even though Tesla itself says, “Model 3 will begin production in late 2017,… ” That’s a long wait, but early adopters aren’t easily dissuaded, as shown by demand for the impressive Tesla Model S. But just how innovative is the electric car?

1890: the party begins

Electric Car

The first four-wheeled electric Vehicle took to the roads of North America in 1890. Eight years later Ferdinand Porsche (yes, that Porsche,) was driving his electric P1, which he followed with the worlds first hybrid car. By 1900 28% of the cars built in the US were electrically-powered. (Admittedly, only 4,192 cars were built in total that year.)

1900 saw the founding of the Baker Motor Vehicle Company in Cleveland, OH. One of many electric car start-ups, Baker prospered, thanks to a reputation for quality, until the arrival of the electric starter.

What really killed the electric vehicle

The Model T launched in 1908, and the rest is history, as they say. Well not quite. Many people weren’t convinced of the benefits of internal combustion. The early gasoline vehicles were noisy, smelly, and hard to start. They had a crank at the front of the engine that had to be turned by hand. When the engine “caught” and started to run the crank would fly around, injuring more than a few automotive pioneers.

Thanks in large part to Henry Ford’s efforts, gasoline powered vehicles were less expensive than electrics. By 1916 a Model T could be had for $650, (not an insignificant sum,) but an electric roadster would run around $1,730. Economics played a part in pushing out the electric car, and Baker Electric were one of many to cease manufacturing, but the final blow was delivered by one Mister Charles Kettering.

Now largely forgotten, (except by the students attending the college named after him,) in 1912 Kettering invented the electric starter. Instantly, this changed the acceptability of gasoline vehicles. Sales grew rapidly while electrics disappeared, until the late 1990’s.

They’re back!

Electric cars were largely forgotten until the late ’90’s. That was when, responding to a clamor for “greener” vehicles, (mostly from California,) GM created the EV1. An unattractive blob, it was slow with a limited range. Sales were miniscule, but it might be argued this was also the dawn of the modern electric vehicle era.

Toyota launched the first generation Prius in 1997. Initially sold only in Japan, it reached the US in 2000 some months after the Honda Insight hybrid. It wasn’t an instant hit but dramatic rises in the price of gas saw car buyers take notice, and sales climbed.

A hybrid isn’t a pure electric vehicle as it carries a gasoline engine, but the growth of hybrids, along with legislation on gas mileage, stimulated interest in electrics. In 2008 Tesla started selling the electric-only Roadster. In 2010 Nissan gave us the all-electric Leaf, in 2012 Tesla launched the Model S, which was followed by BMW unveiling their i3.

The electric car is most definitely back and you won’t need carburetors, or fuel injectors.

O2 Sensors – Engine Performance from a Capsule

O2 Sensors – Engine Performance from a Capsule

Long gone are the days when car engine were simply using 4, 6 or 8 pistons, a carburetor and a few other auxiliary elements in order to make the vehicle move forward. While, from a mechanic’s point of view, such powertrain units were simpler and easier to fix or upgrade, they featured a big downside: efficiency.

More efficient thermal engines needed a way to create a better mixture of fuel and air and make use of better motion delivering mechanisms, all to generate a bigger power output. While various materials have replaced iron in engine construction to ensure a higher degree of kinematic movement, to enhance air and fuel mixture, you would first need to figure out how much of each product gets mixed within the cylinder.

Obviously you can’t just section a running engine in half to check it out; this is how the need of O2 sensors was created.

Where and how does it work?

In case you are wondering, yes, your car is most likely to have at least one oxygen sensor mounted right at the end of the exhaust manifold. It’s just one of the dozen sensors modern cars use in order to increase efficiency and power output; after all, that’s what all is about: getting more and more of it.

If the term O2 sensor or oxygen sensor doesn’t sound familiar to you, it may be because this very same capsule with a wire at the end is also called a lambda sensor.

Does that ring any bells?

The placement of the O2 sensor on the exhaust manifold isn’t random; in fact, that is the best place to create a precise estimate on how much oxygen actually gets used in the air-gas mixture happening inside the cylinders. There are two main cases:

  1. Too much oxygen

When there’s too much oxygen used while mixing air and fuel, we are calling it a lean mixture. What happens is that during the mix, the air to fuel ratio (AFR) exceeds its preset value. To create a better picture, a regular gasoline engine works at an AFR of about 14.7:1. This means that for every part of gasoline, 14.7 parts of air should be used to attain an efficient combustion. If more oxygen gets through, peak pressure inside the cylinder increases and by default, chances of knock increase. When a cylinder knocks, it can basically create a rotational force that opposes the one generated by the crankshaft, generating severe consequences.

 

 

  1. To little oxygen

We’ve found out that too much oxygen is definitely not as good as it may have been initially presumed. However, the other extreme isn’t promising. A low oxygen level within the mixture (an AFR below 14.7:1) won’t allow the entire amount of fuel to be burnt, and thus generate an efficient combustion process. This is called a rich mixture. The immediate result is a considerable increase in fuel consumption; those injectors are pumping more fuel than the available oxygen is able to aid burning.

An oxygen sensor constantly monitors the amount of oxygen output traveling through the exhaust manifold, then sends the acquired data to an Electronic Control Unit (basically a computer for the vehicle) which then adjust the amount of fuel being pushed through injectors into the combustion chamber. Since it’s purely electrical, an oxygen sensor varies its electrical input in order to feed data to the ECU: 0.9V for rich and 0.1V for lean mixtures.

What is it made of?

The probe itself features a ceramic cylinder with platinum electrodes plating both on the inside and on the outside. On top, a metal gauze protects the whole system, like a capsule. It is important to know that oxygen sensors only work effectively while heated at about 600 F (or 316 C). That is the reason why modern sensors also feature heating elements added to the ceramic cylinder, speeding up the heating process. Unlike them, older sensors based solely on the exhaust gas heat to warm up.

Oxygen sensor failures

The best indicative for the wellbeing of an oxygen sensor is the way your vehicle performs. A lower overall performance may be caused by a faulty oxygen sensor, but it isn’t always the case. First of all, it is perfectly normal for a vehicle to exhibit lower performance when cold started. It takes a while for the lambda probe to heat up; until then, since it gets no input from the sensor, the Electronic Control Unit of the vehicle will supply a preset amount of fuel, usually a little above the normal Air to Fuel Ratio.

Electronic Control Units also consider input data from engine coolant sensors when “deciding” how much fuel to inject into combustion chambers; this is why a faulty coolant sensor indicating a higher temperature will cause the ECU to push less fuel through injectors.

If your vehicle traveled more than 100,000 miles, then find out that this equals to the average lifespan of a heated lambda probe. Although you may not feel any serious downshifts in performance, it may actually be a good idea to replace your car’s oxygen sensor with a new one, maybe even opt for a premium product.

 

Premium Oxygen Sensors

Is there an actual reason you should switch to premium sensors or it’s just a new marketing stunt? The truth is, yes, your car can benefit from having a premium oxygen sensor installed. Considering the fact that premium quality sensors are built with higher grade technology and come with various prerequisites such as coated threads with anti-seize compound, fuel efficiency and power output of your vehicle may shift from good to better.

Although premium sensors are mostly after-market products, they are built by the same brands employed by major automakers to develop OEM parts. It is, however, important to check full compatibility with your vehicle before acquiring a new oxygen sensor.

 

 

What Kind of Fuel Mileage Can We Expect

While fuel efficiency isn’t the only factor when deciding on which car to purchase, it is an incredibly important one. Considering the current prices for gasoline, as well as the country’s tumultuous relationship with many oil-producing nations, fuel efficiency can determine your financial future. Rather than changing your plans on which class of car to purchase, you can instead make sure to look into fuel efficiency when making your car decisions.

  • Fuel-Efficient Hatchbacks
    • The vehicles boast some of the best fuel economy in the industry. Many of these vehicles work in tandem with electric engines in order to minimize the fuel needed to power the vehicle. While many of these vehicles can be expensive on the front end, they can end up saving money, depending on the distance you plan to drive your vehicle. The 2015 BMW i3, for example, boasts a whopping 139 miles per gallon (38mpg on gas engine only). Even if you don’t choose to go with an electric car, you might consider another fuel-efficient hatchback. The Toyota Prius is a more affordable option that still gets up to 44 mpg.
  • Subcompact Cars
    • Not everyone is going to prioritize fuel efficiency. Subcompact cars, like the Honda Fit, might be a reasonable option for people looking to avoid hatchbacks and hybrids. The Fit is calculated at 33 overall miles per gallon. Small doesn’t always mean “efficient.” The Scion xb is a small car with only 23 overall miles per gallon.
  • Compact Cars
    • The Honda Civic and Volkswagon Jetta are both on the higher end of fuel economy in their class. The hybrid versions of these vehicles offer the best mileage, while the regular versions are also quite efficient in their use of fuel.
  • Sporty Cars
    • Just because you are looking for a sporty car doesn’t mean you have to sacrifice on fuel prices. Mini Coopers, while sleep and sporty, also offers reasonable fuel efficiency. Mini Coopers maintain an overall score of 30 miles per gallon; however, some sporty cars fare much worse. The Chevrolet Camaro Convertible, for example, gets only 17 overall miles per gallon, which is almost half of that of the Mini Cooper. This just proves that no matter what type of car you are looking for, you need to look into how much money you will be spending on gasoline.
  • Midsized Cars
    • Midsized cars can be a very responsible decision for people who are looking for practical yet efficient vehicles. One of the best options for midsized cars is the Mazda6 Sport. The Mazda gets up to 32 miles per gallon, with the Nissan Ultima close behind at 31 miles per gallon.
  • Upscale/Luxury Cars
    • Upscale Luxury vehicles doesn’t necessarily mean fuel-inefficient. The Tesla Model S, for example, gets up to 84 miles per gallon in tandem with the electric engine. The Lexus ES, which isn’t an electric or hybrid model, still gets up to an overall 26 miles per gallon. The Chevrolet SS, on the other hand, gets only 17 overall miles per gallon.
  • Small SUVs
    • SUV doesn’t have to be synonymous with gas guzzler. These small SUVs offer comfort and size without entirely sacrificing fuel efficiency. The Subaru Forester, for example, gets up to 28 overall miles per gallon, which rivals some of the more “practical” options.
  • Midsized/Large SUVs
    • The Hyundai Santa Fe, which is on the larger end of SUVs, still gets up to 23 miles per gallon. There are also several hybrid SUV options, such as the Toyota Highlander Hybrid, which gets up to 25 overall miles per gallon. Some larger SUVs; however, prove much less fuel efficient. The Ford Expedition, for example, only gets 14 overall miles per gallon.
  • Minivans
    • While minivans can be incredibly practical, they don’t always offer the best mileage. Even the Honda Odyssey, with some of the best mileage in its class, only  gets up to 21 miles per gallon. The Chrysler Town and Country fares even worse, at 17 miles per gallon.

As vehicles continue to evolve, fuel efficiency keeps getting better and better. Even if you aren’t willing to purchase an electric or hybrid vehicle, there are so many options within each class of car, that it’s important to make sure that you aren’t choosing a car that will end up costing you more money than you intended. Depending on how much you drive, fuel can be incredibly taxing on your financial stability. While you don’t necessarily need to make any sacrifices on the class of car you purchase, you might consider paying special attention to fuel efficiency when looking into potential buys. Not only will you save money, but you will be doing your part to help the environment.

Injector Types

Different Injector Types – How Do They Work?

You have probably been driving your car around for years without giving too much thought to the principle of action behind the engine. You don’t need an engineering degree to understanding the basics of an engine. The purpose of a gas-based engine is to transform controlled fuel explosions into kinetic energy, which is further transmitted to the wheels through a gearbox. The fuel is collected through a fuel pump from a tank then it’s delivered and injected into the engine.

The injector

Injectors

 

A critically important component within the injection mechanism is the injector. It sprays a finely tuned amount of fuel into the ignition chamber where a piston compresses it then a spark plug makes it explode and create kinetic energy. As previously mentioned, the amount of fuel sprayed by the injector is highly tuned by the ECU (electronic control unit). Any variation would prove to have a considerable impact over the vehicle performance, usually lowering it.

In order to optimize performance based on the type of fuel used, purpose of the vehicle and to adhere to the latest technological improvements, more than one type of injector has been developed. Currently there are 3 main injector types being used in automotive engine construction: top-fed, side-fed and throttle body injectors.

Throttle body injectors (TBI)

Initially introduced in airplane construction, throttle body injectors are also called single point injectors. Unlike their more Throttle Bodymodern counterparts, single point injectors are located directly inside the throttle body rather than on a rail.

They were the first upgrade of the classic carburetor system, and thanks to its design, a throttle body injection system can make use of mostly the same components as the carburetor did.

Along with their compatibility on older carburetor based throttle systems, throttle body injectors are also relatively cheap to repair or replace when compared with the other available injection systems. However there is also a drawback. Although computer-controlled, due to their emplacement and way of action, throttle body injectors are not very efficient. The fuel is dumped into the intake, creating what is known as a “wet manifold”.

Multi point fuel injection

 

Also known as port injection, multi point fuel injectors are designed to work as a group, with each engine cylinder having a fuel injector of its own. Injectors are placed right outside the intake valve, the fuel vapor is ensured to be delivered completely to the ignition chamber.

This allows a better tuning of air/fuel ration while in the same time it lowers chances of fuel condensing inside the manifold, as it Injectorsometimes happen with the throttle body injection systems.

Even with the high proximity placement of the injector, multi point injection systems still lack a perfect suction of the fuel inside the ignition chamber; it is however, more effective than TBI systems.

Sequential injectors

 

Based on the multi-port injection system, sequential injectors are also assigned one per each cylinder and attached as close as possible to the intake valve. However, unlike regular MPIs, sequential injectors are controlled individually by the ECU (electronic control unit), allowing them to open one at a time.

Sequential injection allows for fuel to be delivered solely when the intake valve opens so it directly travels inside the cylinder chamber. In case of regular MPIs, all injectors fire at the same time regardless the state of the intake valve. Sequential injectors can be timed to spray fuel in the same manner spark plugs are set to ignite it.

Fuel economy is increased with the use of sequential injectors. However, incomplete fuel consumption may arise when injectors are poorly tuned, leaving traces on the intake manifold or over the surface of the valve.

Direct injection

 

Used on more recent engine types, direct injection systems bypass intake manifolds and valves, spraying fuel directly inside the Injectorignition chamber. Computer-controlled, direct injectors are timed to spray fuel differently according to engine type.

Diesel fuel is injected either through a high-pressure common rail connected to injectors. The other option is to use unit injectors which increase the pressure of the fuel within the injector rather than within the common rail.

Ultra lean burn is achieved when using direct gasoline injection (also known as Fuel Stratified Injection – FSI, or Gasoline Direct Injection – GDI) while also completely removing “wet manifold” issues and reducing emissions.

Although they provide more performance and better fuel efficiency, direct injection systems are also more expensive to repair or replace when damage occurs.

 

Side-feed and Top-feed injectors

 

Along with emplacement injection type, fuel injectors also differ according to the way fuel is supplied to them. Injectors can be either is supplied with fuel from the side (side-fed) or from above (top-fed). While the overall aspect may not look very different to the naked eye, there is a series of advantages and drawbacks for each type.

Side Feed InjectorTop Feed Injector

Side-feed injectors are fit inside the common-rail. The rail is fixed either to the engine block or the manifold. Side-feed injectors are constantly surrounded by fuel; given this, they benefit from improved cooling, thus being less prone to damage. The side-feed is the most common used injector type.

On the other end of the barricade are top-feed injectors. Unlike their side-feed counterparts, top-feed injectors are attached between the rail and the cylinder chamber. This makes them easier to replace or upgrade, as there’s usually no need to adjust or replace the common rail as in case of side-feed injectors. However, due to the fact that they are not surrounded by fuel at all times, top-feed injectors may suffer from a lower life expectancy, needing to be replaced more often, especially in high-performance vehicles.

Bugatti

The name, Bugatti, conjures up some mental images that surpass mere mechanical and engineering accomplishments. The name carries with it something almost magical. Today’s Bugattis are famous for speed and power, just as were the earlier models in the 1920s and 30s.

The most iconic Bugatti of all, the type 41 or Royale, was intended to be the most luxurious and biggest car in the world, created specifically for royalty. It was the no-compromise creation of Ettore Bugatti, who cut no corners and made no sacrifices in its design and construction. For example, the engine block and head were not separate as is typical in engine construction, but were machined out of a single block of cast iron. The brake drums were machined as part of the wheels. This was a 7,000-pound beast that was 20 percent longer and heavier than the biggest Rolls-Royces ever built.

The automaker was already world famous as a proven winner in the racing world, having dominated Grand Prix racing for the entire decade of the 1920s. One of the more notable racing victories came with the brand’s second and last win in the 24 hours of Le Mans in 1939. That car was co-driven by Pierre Veyron, the namesake of the later model that today we call the fastest production car in the word.

Meanwhile, in the early 1930s, Bugatti tried its hand at creating the most extravagant road car ever made, and the Royale was the exquisite result. The Royale, in each of its various custom body types, was noted for its aesthetic beauty as well as its performance. They were so unique and so expensive that only six were ever constructed. Because of the Great Depression, they managed to sell only three of the six before abandoning the project altogether.

Long after the Bugatti family relinquished the rights to the name, Bugatti cars are today being produced by the parent company, Volkswagen AG, with the expressed objective of making the Veyron the fastest production automobile in the world.

Volkswagen AG also borrowed heavily from the reputation of the early Royale, and manufactures a model of its own today under that name. Some describe that car as downright ugly, and at the very least it pales in aesthetic comparison to the elegance of the original. But there is no disputing that the model introduced in 2005 as the EB 16.4, or Veyron, was driven to a higher top speed than any other production car in the world, at 252.95 mph in August, 2005.

The car’s designation pays homage to Ettore Bugatti (EB), as well as noting the number of engine cylinders (16) and the number of turbochargers employed (4). That’s right, four turbochargers. And 16 cylinders in a W-configuration displacing eight liters (7993 cc or 488ci) and producing 922 lb ft of torque and 1,001 hp. The power output was another record for production cars. The direct fuel injection, seven-speed gearbox, and four-wheel drive cap the picture creating a car with immensely rewarding power as well as an unsurpassed feeling of quality from its luxurious leather-appointed cabin. But aside from factory employees, almost everyone knows the EB 16.4 as the Veyron.

The carbon-fiber monocoque construction chassis is secured to the road with an interesting ride-height hydraulic system that adjusts to the car’s speed, with three distinct stages. The first is the height while cruising at anything below 137 mph. That height is about five inches (4.92). When the next stage kicks in a rear spoiler raises up as the car drops to 3.15 inches at the front and 3.74 inches at the rear. This “downforce mode” is engaged up to 233 mph. Then at still higher speeds than that, the ride height adjusts to 2.56 inches front and 2.76 inches rear as the spoiler also adjusts to a minimum drag coefficient.

Hit with some unanticipated spending cuts due to a recent emissions scandal, Volkswagen AG is apparently going to be forced to reconsider the 2016 launch of the planned replacement for the vaunted Veyron. So there remains the possibility that Bugatti may relinquish the title of fasted production car on Earth. But the title was questioned by many already, as “fastest” can be defined in many ways beyond simply attainable top speed.

The Veyron is a rocket, there is no question about that. But it is fast despite a serious weight problem. The car is incredibly heavy for a supercar in today’s world, weighing in at nearly 2,000 pounds. While it is faster in a straight line than anything else, it was never intended as a racecar, and would not compete favorably on most road courses against a McLaren f1, or a Ferrari Enzo or LaFerrari, for example. But in large part due to its weight, the strengths of the Veyron include an exceptional feeling of solidity and control. That is largely lacking in all of the other supercars that are more nimble and thus a bit more twitchy. The Veyron handles in traffic like the refined and well-behaved luxury car that it is.

When you do choose to explore that rocket-like acceleration, turbo lag is non-existent due to the massive power output. Wheel spin is also controlled through the four-wheel drive that keeps the wheels firmly planted on terra firma, no matter how fast terra firma is disappearing in the rear view mirror. Some might criticize the car as too heavy to be practical, but since when is practicality a consideration for cars like this? Is a McLaren f1 practical?

Perhaps an interesting side note here, is this. The Veyron sold for in excess of $1.4 million USD. Of course, there were only six of them made, but the last three times one of the original Bugatti Royales sold, the Coupe de Ville Binder reportedly sold for $20 million USD in 1999, the Berline de Voyage sold in 1991 for $8 million, and the Kellner Coupe brought a reported $15.7 million in 1990. Despite Bugatti’s having re-introduced the name, the world will never again see cars like the original Bugatti Royale. But the world will no doubt see a few newcomers looking for the title of fastest production car on Earth.

Direct Injection or Port Injection

Today’s direct Injection is to port fuel injection as port injection was to carbureted fuel supply back when the industry was in transition from carburetors to EFI in the 1970s. There are differences, but the comparison is valid. And as fuel economy standards continue to demand more efficient vehicles, the shift to direct injection is an important one. Just as port injection was a distinct improvement in many respects over carburetion, direct injection is clearly superior to its cousin in all of those same categories: More precise metering; cleaner burning; greater fuel efficiency; and cleaner exhaust emissions.

In recent years DI has come of age, due in large part to the combination of its superiority and the economic realities of our age. Only fairly recently has the technology been available to make DI practical. Today’s computer speeds are fast enough to get the job done, and the environmental demands calling for cleaner emissions make DI a perfect fit for an industry seeking those mandated objectives without sacrificing performance.

How do they compare?

Port injection sprays fuel into the ports behind the intake valves where it mixes with air before the valve opens to admit the mixture into the combustion chamber. The metering was a definite improvement over carburetors. But the next step up is direct injection. DI’s injectors are actually mounted with their tips inside the combustion chamber, so fuel sprays directly into the chamber–not into a “waiting room.”

While port injection represented a far higher fuel pressure than was common in carbureted systems, this also gets a big boost with DI. Port systems typically operate at between 40 and 60 psi, while DI can push the pressure range up to 15,000 psi or more.

Another advantage that is found in some direct injection systems involves the computer’s capability to reduce the amount of fuel given to the injectors during periods when the engine is not under load. When you are coasting downhill, or to a stop, for example, or at idle, the computer reduces the amount of fuel to a bare minimum. This in turn reduces power output, but at these times, power output is unimportant. The other thing that it reduces, however, is still pretty important. It cuts fuel consumption markedly.

So, the advantages are obvious. But DI brings some disadvantages to the table, as well. For one thing, it is far costlier to manufacture. That high fuel pressure requires a far more expensive fuel pump, and with the injectors mounted in the cylinder head they are exposed to far greater heat and the added pressure of the actual combustion process. This means the injectors have to be made of exceedingly high quality materials, which increases the cost even more. Even the fuel lines in direct injection systems have to be beefier to handle the extra fuel pressure. And on a more cosmetic note, DI is also noticeably noisier than port injection, especially at idle speed.

Another potential disadvantage revolves around the build-up of carbon on the valves. In port injection, the fuel is sprayed onto the back sides of the intake valves. Since gasoline contains detergents, this actually serves to keep those valves cleaner. The valves in a DI system get no such fuel bath, and so they may require service earlier. It is still early in DI’s young development, so we don’t yet know how serious a problem this may become. Early signs of carbon problems have cropped up. Mostly (but not exclusively), this has been seen on a few specific engines. The Audi V6 and the Audi/Volkswagen 2.0 liter are, so far, the most likely engines to experience this carbon problem. This is a pretty expensive problem to cure. And as mentioned, it is still early in this game, but this may prove to be a distinct advantage for port injection over DI.

The most obvious advantage of port injection is the savings in cost of manufacture, which gets passed along to the buyer in the form of lower sticker prices. Cheaper injectors, fuel pumps, and fuel lines make the shopper’s sticker shock less of a problem.

Some automakers are cleverly blending the two systems together in certain engines. Instead of the Frankenstein effect that some might suspect, this actually works out pretty well. The Subaru BRZ and Scion FR-S offer such systems, as do certain variations of Toyota’s 3.5-liter V-6 engine. These combination systems blend the benefits of each so that the port system deals with clean start-up and other low load conditions, and then the DI kicks in under the load of acceleration. You might think this is the way to go, but the biggest difficulty with DI is still the cost differential. If you have a combination system, you still have the high cost of DI with a little added cost on top of it to also support the port system.

With the undisputed superiority of DI in terms of efficiency, emissions, and performance, there is little doubt that the future of port injection is probably doomed to extinction at some point. Even if de-carbonizing the intake valves becomes a problem for many DI engines, the likelihood is that technology will find a way to overcome the problem more effectively than returning to port injection as a solution.

Cold Starting

Cars, while hardy, can be finicky at times. When your engine is below a certain temperature, your works to add fuel to the air mixture to start the vehicle. Positioned on the intake manifold, the cold start injector helps refine the mixture in the engine’s cylinders for better burning. However, when your car starts having problems, the culprit is often this valve.

  • What is it?

A cold starting problem occurs because an engine typically needs more fuel to start when cold than when hot. This condition is referred to as “cold start enrichment.” The problem can either be with starting the engine or the car running when it is cold – both tie back to the same cause. If the car doesn’t have the proper enrichment when it’s cold, then the problem will persist.

  • What should I watch for?

Things like the engine flooding, smoking, starting and stopping, or the vehicle won’t start or is difficult to start are definite giveaways that something is wrong. If the engine is flooding, then there is a chance that the cold start injector is leaking, allowing too much fuel to flow to the cylinder. When the pressure in the injector is too low, it will cause a heavy fuel/air mix to smoke through the engine. Your engine starting and stopping is an indication that the pressure of the injector is too high. A vehicle that won’t start means that there is no fuel reaching the engine and your injector could be clogged. Starting your vehicle and being met with hesitation or cranking might be a sign that the injector needs to be reset and the thermometer start interval reduced.

  • How do I fix it?

It is recommended that your fuel injector be cleaned regularly by a professional. By regularly, we mean every 36 months or 45,000 miles. If this isn’t done, there is a higher chance for your injector to become dirty or clogged which will cause problems like your vehicle’s difficulty cold starting or running. There are ways to clean cold start injectors, but it won’t be the thorough clean necessary to prevent issues. Cleaning your cold start injector should be done by professionals.

Oxygen Sensor

A Check Engine light most often means one of the oxygen sensors in the exhaust system is sending the OBDII system an error code. Many times the solution is to replace the sensor itself, which can be both difficult and expensive. Less often, the sensor is actually doing it’s job, signaling a problem upstream in the fuel injection system.

In modern vehicles fuel injection has become very complex, with multiple sensors and valves working together to optimize the fuel-air ratio for low emissions and good performance. A fault in any one of those could lead to a oxygen sensor turning on the Check Engine light. However, with an understanding of how these components work together it’s possible to carry out some quick checks. This starts with learning how sensors in the exhaust can monitor engine combustion.

Oxygen sensors and combustion

Every vehicle manufacturerd since the mid 1990’s has two oxygen sensors in each exhaust system. (So that’s four on a V8-powered vehcle like the Chevy Suburban or Silverado.) These are mounted in the exhaust, one each side of the catalyst. (On some vehicles the upstream sensor is actually in the exhaust manifold.) Their job is, as the name suggests, to sense the amount of oxygen in the exhaust gas.

This oxygen comes from the air drawn in through the induction system and into the cylinders. At some point on its journey, either in the throttle body, the inlet ports, or directly in the cylinder, the injection system sprays gasoline into the air, in a ratio of 14.7 parts air to 1 part gas.

Maintaining this air-fuel ratio is important because it’s the mixture strength that burns most efficiently. All the gasoline and almost all the air will be consumed and there will be no unburnt hydrocarbons going down the exhaust. Should the mixture be richer, say 14.0:1, (meaning less air and more gas,) some of the gasoline won’t be consumed during combustion. Less power will be produced, emissions of noxious gases will be higher, and it’s possible the catalyst will be damaged. Conversely, too much oxygen means the engine is running lean, (the O2 isn’t all being consumed during combustion.) This will reduce power output and can potentially damage the engine.

Sensor construction

At the heart of most oxygen sensors is an element made from Zirconia, (some use Titania, but it works in much the same way.) Zirconia is able to conduct oxygen ions when it gets hot and this effect is used to sense the ratio of oxygen in the exhaust gas to that in the air. The way this works is that the outside of the sensor is in contact with the exhaust and the inside contains reference air. A thin layer of platinum coats both sides of the Zirconia, and acts as a pair of conductive electrodes.

ECU signals

Oxygen ions entering the Zirconia cause the voltage between the two layers of platinum to vary. Low oxygen levels result in high resistance, and so high voltage. When more oxygen is present the voltage is lower. The Engine Control Unit (ECU) monitors this signal, adjusting the air-fuel ratio as necessary by changing the length of time for which the injectors are open.

Inside each injector is a solenoid whose job is to open and close a valve, allowing gasoline to spray through a a small hole or holes. (Some of the newest injectors use a piezo actuator to open and close the valve.) On a signal from the ECU the injector opens, allowing gas to spray until a second signal tells it to close.

Fuel injection pressure

The injection system works by holding gasoline under pressure behind the injectors. In port and direct injection engines this happens in a steel pipe called the fuel rail. The fuel pump supplies the rail with more gas than the engine can use, returning the excess to the tank. At the output end of the rail there’s a spring-loaded valve called the fuel pressure regulator. This holds fuel in the rail, only opening when the pressure exceeds the spring setting.

Oxygen Sensor

The twist in this is that air pressure at the inlet port varies depending on how hard the engine is working. Technically, this is referred to as vacuum because it’s less than atmospheric pressure. To maintain the pressure differential the spring load in the regulator must be adjusted to account for changes in this vacuum, and this is done with a vacuum hose connecting it to the inlet manifold.

Vacuum and the Check Engine light

If there’s no vacuum acting on the regulator it needs higher pressure in the rail to make it open. Higher pressure means more fuel spraying when the injector is opened, and that leads to an over-rich air-fuel mixture.

So, here’s something to look for when the Check Engine light comes on: find the fuel pressure regulator and verify that it’s hooked up at both ends. If it is, the problem is either a bad sensor or something else is going on, but at least you’ve eliminated one possible cause.

Jeep Fuel Injectors

Jeep Fuel Injector
Fuel injectors rarely go bad but when they do, they can give you serious headaches. Don’t worry however, it’s not as bad as you think. A bad fuel injector isn’t that serious and it’s almost never terminal, it’s just a real issue to solve if you don’t know what you’re doing. Thankfully there are a lot of articles online, and this is one of them. Specifically, this is an article regarding Jeeps (1986-2010).
One great thing about Jeeps is that they’re extremely easy to work on. Because the engine bay is large and the actual engine isn’t crammed into the bay, you have a lot of room to carry out every procedure. The fuel injectors are very accessible, making it less of a challenge for a novice.
Diagnosing a bad fuel injector is relatively simple. For starters, the most obvious tell-tale sign is a misfire, either in one or more cylinders. When checking for a faulty fuel injector, get the engine to operating temperatures if you can. If it won’t start, you don’t have to worry about achieving operating temperatures.
The easiest way to check fuel injectors is by using a multimeter. Disconnect the fuel injectors and attach the test leads to the male spade terminals. Measure the resistance (Ohms) of the injector. Ideally, you want to find out what the resistance should be from a manual (often it’s between 13.3 and 15.7 for V6 Jeeps), but if you can’t figure that out, there’s another way. Simply measure all of the fuel injectors. That way you’re getting a pretty decent estimate as to what the average reading should be and you can track down and isolate a single fuel injector should it deviate from the norm.
If the resistance is roughly the same for all fuel injectors (within the allowed tolerance), the problem’s not in the fuel injector. If one fuel injector reading deviates too much, you know that it’s faulty and that it needs replacement.
The second method requires a vehicle equipped with OBD II. Later model Jeeps have it, but make sure to check if yours does. The procedure is simple. You attach an OBD reader to the port and it tells you all of the faults (if there are any). In 90% of the cases with a faulty fuel injector it will print a misfire rather than just a code for a bad fuel injector (check to a manual or online guide for specific Jeep codes).
To ensure that fuel injectors last you a long time, always purchase OEM ones or fuel injectors from a reputable manufacturer. The cheaper alternatives may sound tempting, but they will cost you more in the long run. After all, a fuel injector isn’t something which needs replacing that often. It’s better to buy a decent quality one from the get-go, rather than go through a pair of cheaper ones before finally switching over.

Ford Truck Fuel Injector Replacement

Ford Truck Fuel Injector Replacement
Ford Powerstroke engines have been the heart of Ford Trucks for over two decades now. Boasting the common 7.3 liter displacement, they have been the heavy duty mules of the American farmers and industrialists since 1994.
Just like with any other diesel engine, the power output heavily depends on the injectors – their proper function is vital to the engine. Whether you want to boost up your Ford Truck power output or to revive a slowpoke of an engine, replacing fuel injectors could be the best solution. However, before you begin, there are some prerequisites to consider.
Do your Ford injectors need replacement?
It’s pretty obvious that, if you’ve bought a truck, it isn’t going to be a garage queen anytime soon – trucks are built to pull and carry, earn money. Most trucks used regularly tend to go over 100,000 miles on the tachometer after a few years of usage.
While, yes, Ford Powerstroke engines are built to last, there is only so much a mechanical component can withstand before ceasing or lowering yield. Sluggish acceleration, strange rumbling, and RPM variation at idle: these are all symptoms of faulty fuel injectors. If this is the case for your truck, then you should prepare to replace your injectors.
Where to get Ford Truck Injectors
Having a quick glance at Google results will reveal that there are quite a bunch of aftermarket shops offering new or refurbished injectors for 6.0 liter and 7.3 liter Powerstroke truck engines. However though, you should be very careful in choosing replacements: not all parts feature the same quality as OEM ones, thus you might cause more damage to your engine rather than getting it to work better.
In the left picture, you can see an OEM Ford Powerstroke injector for 7.3 liter units. It is highly recommended to check with your local Ford dealer for injector replacements, although you are warned: OEM parts don’t come cheap – sometimes the price will be twice or three times higher than what you would pay for an aftermarket part.

Replacing injectors for power boost
If your Ford truck doesn’t show any sign of performance deficit due to currently installed injectors, you might still want to replace them in order to achieve a higher performance output from the engine. Still, this can’t be done right away, unless you are okay with causing long-term damage to your cylinder head and engine block.
While your Ford Powerstroke cylinders are by default able to cope with performance injectors, it is highly recommended to secure your engine’s cylinder head by replacing OEM bolts with high performance one. Most users highly recommend ARP cylinder head bolts – not only that they are relatively easy to find and come at decent prices (about $190 for a set), but ARP is the leading performance parts manufacturer for the racing industry for over three decades.
Once you’ve upgraded your engine’s cylinder head bolts and added performance injectors, you should do a detailed diagnosis of the truck to make sure everything works the way it should.