Subject: | Intermittent Stall When Coming To A Stop or Engine Chuggles prior to a Stop, Hybrid DTC P1A6F |
Models: | 2007-2008 Chevrolet Colbalt, Malibu, HHR |
2007-2008 Pontiac G5, G6 |
2007-2008 Saturn Aura, Vue |
equipped with 4T45E transmission including hybrid |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
The customer may have a complaint of a chuggle or stall when coming to a stop. This may be cause from momentary to fully applied torque converter causing excessive loads on the engine.
BAS Hybrid Vehicles
If this condition is experienced on a BAS hybrid the engine tachometer will drop to Zero and not Auto Stop. There would not be a command for an auto-stop. The engine may restart using the 12v starter and set a DTC P1A6F.This may lead the technician to incorrectly suspect the hybrid components.
A partially or momentarily applied TCC maybe caused by a restriction in the transmission cooling system
Please note a possible restriction in the transmission cooling system may not allow a sufficient volume of fluid to properly release the TCC.
To properly diagnose for possible restriction in the transmission cooling system, complete the following:
Check the transmission cooler for restriction.
Check the transmission cooler lines for bends or kinks
Check the transmission cooler line fluid passages (behind the fittings) for any restriction.
Repair the concern as needed.
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.