Mechanical Fuel Injection Service Information

A vehicle's fuel injection system delivers pressurized fuel into an internal combustion engine, using a fuel pump, pressure regulator and a series of sensors that control the amount of fuel supplied to the engine. Over time, the fuel injectors can become clogged and must be serviced or replaced.

Problems

Basically, a fuel injector is like a spray nozzle, squirting fuel through a fuel line. When the car's computer activates the injector, it causes a spring-loaded valve to open, allowing fuel to flow through the fuel line. Over time, carbon deposits can build up on the spray nozzle and restrict the flow of fuel, causing the engine to hesitate or even stall. This requires immediate service.

Replacement

In extreme cases where the fuel injectors are so badly clogged they can't be cleaned, they need to be replaced. As of 2010, the cost of new fuel injectors is $60 to $100 for domestic vehicles, and $125 to $175 for import vehicles.

Cleaning

Most fuel injectors can be cleaned. One option is to clean the injectors while they are still installed in the vehicle using a pressurized solvent to loosen and remove the deposit build-up. Another more expensive option is to remove the injectors from the vehicle and clean them using a reverse flushing technique, which removes debris caught inside the injector.

References

• Yahoo! Autos: My mechanic says my injectors are dirty and need to be cleaned. What does that mean?
• Edmunds: Tom's Corner Garage: Cleaning Fuel Injectors; Paul Seredynski; August 2009.
• 2CarPros: How Fuel Injection System Works.