Fuel Injection System

Fuel Injection System Repair

A faulty fuel injection system can have a serious effect on your car’s performance and can lead to untimely car break downs and significantly expensive car engine repairs. A faulty fuel injector can also cause a significant decrease in the efficiency of your fuel consumption. The following article will discuss several key symptoms of a faulty fuel injection system. It is always best to have your car repaired if you notice any of these symptoms.

What Are Signs That You Have Problems With Your Fuel Injection System?

Fuel Injector Servicing Kitchener Waterloo A faulty fuel injection system manifests itself in several ways.

1) Rough Idling

The job of your fuel injector is to put fuel directly into your engine cylinder via the fuel rail before it is burned during combustion. If this process is not done efficiently, the result will be a choppy engine while your car is sitting idle. Another key sign is a significant loss of power on acceleration because the fuel flow is restricted. The reason the power loss is noticeable is because there has been a significant build up of deposits in the fuel injection system, and each cylinder is not receiving its full allotment of gasoline. These buildups are the result of cold-start operation, where the vehicle never has a chance to warm to proper operating temperature, and gum and lacquer block the injector.

2) Gasoline Leak

The next common symptom of a faulty fuel injection system is gasoline leaks. Fuel injectors can crack and break, which results in a gasoline leak. If your faulty fuel injection system is causing a gasoline leak, the spilled gasoline will be both visible and will cause a smell. A cracked fuel rail could also cause a leak.

3) Poor Fuel Economy

Another common symptom of a faulty fuel injectors is poor fuel economy. As mentioned earlier, a cracked fuel injector or fuel rail can cause a gasoline leak, which in turn will decrease fuel economy. A faulty fuel injection system may also inject too much gasoline into the engine, which is wasteful, less efficient and will lower your car’s fuel economy.

4) Surging Engine

If you feel your engine surging, your car may be suffering from a faulty fuel injection system. A surging engine is caused by too much gasoline being injected into the engine. This can cause the engine to surge too fast and then accelerate too slowly. To you, the driver, this condition will feel like an up and down motion.

5) Misfiring Engine

Another symptom of a faulty fuel injection system is a misfiring engine. This will occur if your fuel injector is not sending in enough gasoline into the engine. This symptom may also be caused by clogged fuel injectors. To you, the driver, the misfiring engine will feel like a delayed acceleration when you touch the accelerator.

Servicing Your Fuel Injection System

A fuel injector is nothing more than spray nozzle. With mechanical injectors, a spring loaded valve allows fuel to squirt out of the nozzle when line pressure overcomes spring tension that holds the valve shut. With electronic injectors, a spring-loaded solenoid pulls open a pintle valve or ball type valve when the injector is energized by the computer. This allows the pressurized fuel in the fuel rail to flow through the injector and squirt out the nozzle. Injectors come in a variety of styles. Early Bosch style injectors have a pintle valve and are the ones most prone to clogging. In 1989, General Motors introduced its new “Multec” style injectors which have a ball valve design and are claimed to be more resistant to clogging. Other injectors have a disc-valve design that is also said to resist clogging. “Dirty” is actually a misnomer. Rarely are injectors clogged with dirt. Rather, they are usually clogged or restricted by a buildup of fuel varnish deposits. This reduces the amount of fuel that the injector sprays, which in turn may cause the engine to run lean and misfire, hesitate or stall. The truth is ANY injector can clog. Nobody’s injectors are immune to this kind of problem, but some are obviously better than others. Problems can occur even with a slight buildup of deposits. Because the injector orifice is so small, it doesn’t take much crud to restrict the flow of fuel or to disrupt the spray pattern. For good combustion, the injectors must produce a fine cone-shaped mist of fuel vapor. Wear or deposits in the nozzle can create “streamers” of liquid fuel that vaporize and burn poorly. This, in turn, can cause hesitation, emissions and performance problems.

Keeping Injectors Clean

The best way to minimize or eliminate the need for cleaning your fuel injection system is to use a quality brand of gasoline that contains sufficient detergent to prevent varnish buildup. Most brand name gasolines today have enough detergent to do this. As a rule, premium grades usually contain a somewhat higher concentration of cleaners. You can also use fuel tank additives to keep your injectors clean. Such products really aren’t necessary if you’re using quality gasoline. But if you’re buying the cheapest gas you can find, using an additive might be a good idea.

Injector Cleaning

If your injectors do get clogged, the cure is cleaning — or replacement if they’re too badly clogged to respond to cleaning. Injectors are expensive to replace. New domestic injectors sell for $60 to $100 each, with new import injectors fetching $125 to $175 each. Injectors should only be replaced as a last resort. If your injectors are clogged, they can be cleaned with pressurized solvent, or removed for off-car cleaning. There are also fuel tank additives that claim to clean clogged injectors, but the cleaning such products do is usually minimal. So save your money and use it for a professional cleaning. There are do-it-yourself on-car injector pressure cleaning kits that are similar to the equipment professionals use. But some of these kits can be tricky or even dangerous to use. Our advice is to let a professional do it. On-car injector cleaning involves feeding solvent under pressure into the injector fuel rail or supply line. The concentrated solvent passes through the injectors and loosens and washes away the accumulated varnish deposits. The results are usually good, and make a noticeable difference in idle smoothness, emissions and fuel economy. If your injectors are really clogged and fail to respond well to on-car cleaning, off-car cleaning using special fuel injection cleaning equipment would be the next logical option. Some of this equipment is designed to “reverse” flush the injectors so any debris that’s trapped inside the injector or above the inlet screen will also be removed. Off-car cleaning also allows a mechanic to observe the spray pattern of the injectors to make sure there aren’t any streamers or problems. Off-car cleaning is more expensive because of the labor involved to remove the injectors, but the results are usually better. Do you need your fuel injection system serviced? Give us a call to get set up with an appointment right now! We offer top of the life fuel injector service that will get your system cleaned out and functioning at peak performance.

Take your car or truck to DNA Automotive for the best and most cost effective preventative maintenance and car and truck repair in Kitchener-Waterloo. Certified Mechanics and the Best Car Repair rates in Kitchener-Waterloo! Quality Repair Service - Quality Parts.

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