Harsh Coast Down Shifts - keywords 07217A 07274 bind braking campaign coast concern down engine excessive fast flat flare hesitate learn MH2 MH4 MH6 MY9 procedure shift slop spot
| Subject: | Harsh Coast Down Shifts |
| Models: | 2007-2008 Saturn Outlook |
| 2007-2008 GMC Acadia |
| 2008 Buick Enclave |
This PI was updated to advise of calibration. Please discard PIP4315A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Customer comments of harsh coast down shifts, excessive engine braking on decel, or hesitation in the 40-45mph range after campaign 07217A or 07274.
Recommendation/Instructions:
Shift adaptives learn out of range causing two gear ratios to overlap more than normal.
Reprogram the TCM and ECM using the SEQ selection from TIS2WEB, SPS Pass-Thru method release 3.5 (2008) or greater.
Perform the fast learn procedure to learn transmission adaptives.
Important: If fast learn does not complete, a no drive or reverse condition can occur, see PIP4203
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.
