|SUBJECT:||High-Pitched “Chirp”, “Squeak” or “Cricket” Sound from the Engine|
This bulletin provides a procedure to address customer concerns of a high-pitched “chirp”, “squeak” or “cricket” sound heard coming from the engine’s Direct Injection (DI) high-pressure fuel pump. Not all DI pumps may exhibit this sound. Some vehicles may have components which in combination with certain fuel temperatures and / or formulations, may result in aeration of the fuel within the body of the pump and cause this sound. This result is non-detrimental to the vehicle. Production changes have been made to eliminate the source of the sound.
IMPORTANT: A “clack” or mechanical “ticking” sound also made by operation of the highpressure fuel pump is considered to be a normal operating characteristic and no attempt should be made to repair it.