Knocking / Rattling Noise From Under Hood Area After Remote Start - keywords 3.6L 6-speed bolt converter clunk cold disengage engine engaged full intermittent line MH2 noise pressure RVS rattle start

This PI was superseded to update models and model years. Please discard PIC4773.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

A customer might notice a noise coming from the engine compartment ONLY after performing a remote vehicle start (RVS). This noise may be described as a knocking, rattle, or even sounds like the starter is staying engaged after the engine has started. This noise could be caused by the torque converter bolts being loose/cross threaded. The main reason this condition is only heard after performing a remote vehicle start is the transmission control module (TCM) is not powered up via GMLAN when the vehicle is in a RVS state. This causes the transmission to be at full line pressure during a remote vehicle start event.Consequently, the condition caused by the loose bolt/cross threaded condition is more likely duplicate.

If you have the condition above please inspect the torque converter bolts for being loose/cross threaded. If either concern (loose/cross threaded) is present, it is highly recommended that you replace the bolts with new ones.

Note: If the bolts are just loose, then torque them to specs per SI-2000 Document ID# 1747824

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.