96 GMC Jimmy P0108

Need help. Recently received a code of p0108 - Map sensor high input voltage. The vehicle does not shift into passing gear when throttle is mashed and receiving major spark knock.
So far we have:
- checked timing set at -1 degrees
- installed new map sensor
- Recently have had the transmission rebuilt, shift problemn may not be related.

Any ideas where to check next? What would give the map sensor a high voltage input error.

Need help. Recently received a code of p0108 - Map sensor high input voltage. The vehicle does not shift into passing gear when throttle is mashed and receiving major spark knock.
So far we have:
- checked timing set at -1 degrees
- installed new map sensor
- Recently have had the transmission rebuilt, shift problemn may not be related.

Any ideas where to check next? What would give the map sensor a high voltage input error.

Did the check engine light come back on?

Yes, the check engine light comes back. Same code. Any ideas at all?

With MAP sensor replaced, I would have to think you might have a Computer problem.

The shifting thing is not related, but why haven't you taken it back to the guys that rebuilt it?

Thanks for the reply. He believes there may be a short in the computer that is affecting the shifting problem also. He is checking on a kit made by GM to fix the tranny problem. We were not sure whether the map sensor code problem could affect the electronics for the tranny. Ever heard of the a kit for that? Maybe a new computer? Any ideas on costs associated with getting a new computer?
Again thanks for any input.

Forgot to mention, that tranny guy believes that the downshift problem probably burned up the tranny. He could not find anything inside that would have. Just thought I would mention.

Watch it, it sounds like they are going to blame it all on the MAP sensor.

Transmission will not be affected by a MAP error like that.