| Subject: | Engine May Stall at Idle When Tech 2 is used to Energize O2 Sensor Heaters |
| Models: | 2006 Buick Rainier |
| 2006 Chevrolet Trail Blazer |
| with 4.2L Engine (RPO LL8) |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
During O2 heater diagnosis, some technicians may find that the engine stalls or runs rough when a Tech 2 Scan Tool is used to energize the O2 sensor heaters at idle.
Recommendation/Instructions:
At this time, this is a characteristic the Tech 2 software. This function will be removed from the Tech 2 in a future software release and the related SI diagnosis will be rewritten to diagnose the O2 heaters without using this function. Continue to
diagnose and repair the vehicle as necessary. Do not replace any parts in an attempt to repair this Tech 2 software concern.
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.
