Medic0893
Newbie
Appreciate the info. Baseline info: the trans was rebuilt about 20k prior to the carb swap. Always ran and shifted fine. I’m not a big believer in coincidence…No problem. Electricals include the harness, shift solenoids, electronic pressure control solenoid and pressure switch manifold assembly.
MLPS = manual lever position sensor...Here's some more detailed info:
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Your downshifting issue is likely TPS, especially if it's aftermarket as they can be tricky to get dialed in. It can also potentially be your 3-2 control solenoid but I'd def rule out the TPS first before swapping in another solenoid...But if you do have to drop the pan, I'd replace everything electrical/electronic down there.
Initially I used the HGM Acculink TPS with no luck. I recently installed the Holley TPS but didn’t get a chance to dial it in. It runs and shift fine (actually better than the HGM) through all gears in surface streets, but same issue on the highway. I read the signal should be 0.45 - 5.0 for the lever sweep… sound right? I did replace the input speed sensor after reading it might help. Initially I thought that was my solution, but over time it seems not to have made the difference I thought it would. I’m gonna back-pin the signal wire and see what it’s putting out. When I did that with the HGM the numbers were crazy (nothing less than 0.75) HGM was worthless, no support unless you buy their $1000 computer.