I owned a 1984 turbo standard for 3 years now. It always a little rough when start but runs great when I start driving. I recently installed intercooler and it ran fine for 5 minutes then loss of power and rough idle. Found out I have a bad TPS then replaced it and the car runs better until it gets warm. It wouldn't pick up until I rev to 3500rpm. It only does this when when warmed up. Hesitation goes away if I ride the clutch and rev pass 3500rpm but eventually come back after driving for about 15mins.
What I have done since the issue : replaced TPS, cleaned AAC, replaced MAF.
Note: I also notice oil pressure drop during hesitation. My idle at smooth running condition is 1000rpm. Drops to 800 to 900rpm while hesitate with oil pressure drop. Turbo only boost at 3000rpm since this issue (boost at 2500rpm before).

Any tips,advices and guidance is much appreciated.

 

You can drill out the rivets on the back of that TPSwitch its just 2 contacts idle and moderate throttle and adjust them. 88 up was a sensor. A press. Guage to read the boost is helpful in diag.
​​​​​​​any pics of the intercooler?
Just weak no miss

 

I'll try to post some pics. As for the TPS. I have replaced new one a week ago. Weird thing is when hestitation happens, I pull over and unplug the TPS while engine is running and it made no difference. Could this be the new one also not working? Will try to open the TPS per your advice since I bought 2 of them anyways. Will keep you posted. Thanks

 

try the old one , usually the contacts get spread too far apart
it is supposed to have no contact with either for a bit .
fuel all good hiigh octane

 

forget the tps. probably the CHTS