Expert: autohelp - 7/27/2005

Question
1994 Chevy S10, 4.3 V6, 4x2, 125000 miles.
Sometimes when starting off, normal acceleration, hot or cold, level or hill, engine races and transmission does not shift until throttle is lifted.  May repeat thru additional gears. Once in top gear works ok and will downshift ok. Shifts ok most of time.
Had transmission checked, pan pulled, no residue, no burnt fluid, installed new filter and fluid.
Ran transmission diagonistics and checked ok.  Suggested needed throttle position sensor.
Chevrolet dealer says TPS is not servicable and not problem.  Wants to install rebuilt transmission.

Answer
TPS is NOT your problem. The trans is in the early stages of burning the clutch plates and is not yet evident by fluid color or has burnt enough of the clutch plates to show debris.


problem could be in the clutch packs, the valves in the valve body or the pressure sensors. If the pressures are all showing OK, Then it is time to pull the trans out and rebuild it.