Enclave AWD V6-3.6L (2009)
Fuel Injector: All Technical Service Bulletins
Fuel System - Clicking/Ticking Noises On Cold Start Up
INFORMATION
Bulletin No.: 07-06-04-025D
Date: January 07, 2010
Subject: Information on Clicking/Ticking Sound/Noise Heard During Cold Start, Sound/Noise Decreases But Continues as Engine Warms - Normal
Operation of High Pressure Fuel Pump and Injectors
Models:
2009-2010 Buick Enclave
2010 Buick LaCrosse
2008-2010 Cadillac CTS, STS
2010 Cadillac SRX
2009-2010 Chevrolet Traverse
2010 Chevrolet Camaro, Equinox
2009-2010 GMC Acadia
2010 GMC Terrain
2010 Saturn OUTLOOK
Equipped with 2.8L, 3.0L or 3.6L VVT Direct Injection V6 Engine (VINs 4, G, D, V - RPOs LAU, LF1, LLT)
Supercede:
This bulletin is being revised to include additional models and engine RPOs. Please discard Corporate Bulletin Number 07-06-04-025C (Section 06 -
Engine/Propulsion System).
The 2.8L, 3.0L and 3.6L SIDI engines (RPOs LAU, LF1 and LLT) use a direct injection fuel system that operates at very high fuel pressures. A direct
injection fuel system produces a rapid clicking and ticking sound that can be heard from the engine compartment. The sound is more evident when
outside around the vehicle or when the hood is open. The sound is more noticeable during idle and is more frequent during a cold start, but lessens once
the engine is warm. The rapid ticking noise on cold start up is the fuel pump (located on the rear of the left cylinder head) building up high fuel pressure.
When the engine warm-up is completed, the high pressure fuel pump will continue to tick at a lower rate of approximately one tick per second during
idle. The clicking sound is the fuel injectors pulsing on and off under higher fuel pressures. These sounds are the results of a normal direct injection fuel
system operating properly.
DO NOT attempt to repair or replace any parts for this kind of clicking or ticking concern. The clicking or ticking sound is not indicative of any
concerns with the engine or the vehicle. You may wish to give the customer a copy of this bulletin.
Disclaimer
