I'm in the process of swapping my 91 T2 engine into my 91 vert. Everything is swapped in (engine, harness, ecu, trans, rear, etc.), but now the car won't idle. We tried to adjust the idle screw and we tried to check the timing but can't because it won't idle at or near 750 rpm. The T2 AFM is plugged in, seems to be ok. We checked for vacuum leaks, and their don't seem to be any. Any ideas on what may be causing it to not idle? My thoughts are either a vacuum leak or the TPS, but that is pure speculation. Also, the fuel pump doesn't sound like its turning on when you turn the key to the "on" position. We used the jumper location in the engine bay and then it turned on. Its obviously working because the car runs, but I thought it may be part of the problem? Any input would be greatly appreciated.

 

Have you checked to see If you've got spark? I'd check that first. Even with the Fuel Pump jumpered, you do not hear a whirling from It you say? I'd look Into that aswell.

 

The fuel pump does work when its jumpered. Its only when its not jumpered that I don't hear it running when the ignition is in the "on" position. I should definitely check for spark, but like I said the engine runs when we hold the throttle but won't idle when we let off the throttle. Thanks for the help.

 

you changed your map sensor on the strut tower? if it holds no idle at all it very well could bea vaccumm leak.

 

If you mean the boost sensor (or pressure sensor as its called in the FSM) on the strut tower, yes we changed it. I might just take it to a mechanic Wednesday if I have to, but I'd really like to solve this myself if possible. Any other ideas anyone?

 

Once more everyone........the fuel pump runs: (A) when the key is held to START. (B) when the engine actually starts and runs, that's when the afm/ECU make the fuel pump electrical circuit. (C) if the key is just turned to ON, the fuel pump does NOT run, unless the engine is running.

I was going to bet on the boost/pressure sensor also. Oh well. I was going to suggest that if the n/a boost sensor was on a turbo, it don't hardly work very well(ya lik

 

is the engine ported? sometimes when they are ported they wont idle correctly and it tends not to be a big deal. but if it is a vaccum line.......good luck because there are so many and if there is just take the rats nest of lines out

 

No, the engines not ported. My other car has a ported engine and it idles beautifully. I dunno, I'm gonna check the BAC, TPS, and check for vacuum leaks tomorrow with starter fluid. Hopefully I'll find something.