86 GLHT
TII swapped to 87 TII, re pinned LM and Map under the hood.
Car starts and idles fine, under very light throttle it will drive as normal but when there is a load put on it the car bucks and kicks like overboost but its not overboost. The car threw a code 54(fuel sync) early on but recently it has gone away and hasnt come back. When the code 54 was thrown I swapped out the HEP for 6 different ones and no change. I then went through the wiring diagnostics check for 8+V in each pin and found that when probing the grey connector while it is unplugged I get 8.77V from the Orange to the Black/Light Blue. But only 0.54V when probing the Orange to the Tan/Yellow wire. According to the diagnostics when this is found you check for continuity(resistance) between the terminal and pin 17 on the blue connector. I did this and there is perfect continuity, 1.5ohm of resistance. The manual says that if no voltage is found and there is under 5ohms of resistance replace the LM. We have tried 5 different LMs and no change. Now code 54 is back but I have now replaced all the following parts with new units, LM (new), Power Module (new), HEP (new), Fuel Pump (new), MAP (new) and also thought maybe it had fuel delivery issues so put a fuel pump in a bucket and jumped the pump straight from the battery and car still does it, plus before that even bypassed ASD Relay and same thing????
Any suggestions would be greatly appreciated.....
I figured I'd add that when the car was still stock (TI Suck through) it worked fine the car drove well and never had any issues.