Injector O-rings are flat plastic or rubber rings in a vehicle's fuel injectors. Injector O-rings provide vacuum pressure for the injectors to work properly so that no outside air leaks into the injectors. They also prevent the car from leaking oil. Bad fuel injector O-rings can damage a car over time and inhibit the vehicle's performance.
Idling and Misfires
If your car is idling roughly, too fast or misfiring, this could be an indication that your vehicle's fuel injector O-rings are faulty.
When performing a check under the hood, inspect the fuel injectors. If they are leaking, this is a sign that the fuel injectors need to be replaced. If this is the case, the O-ring fuel injectors are not providing a proper seal. If you have difficulty finding the O-rings, first look for the fuel injectors. There will be a metal tube that holds the fuel injectors in place. At the bottom of the fuel injector, you will see the circular O-rings. They are held in place by a spring clamp.
Leaking or Spraying from Injectors
When idling the car, look under the bonnet. See if there is any leakage or misting from the fuel injectors. If so, this may be an indication that it is time to repair the fuel injectors' O-rings.
Sometimes, the only way to make sure your fuel injectors' O-rings are not damaged is to take them out and inspect them. If the plastic or rubber ring is split or stretched, it needs to be replaced. Cracking also indicates a worn O ring.