I am just curious. I have a little device connected to my wiring harness that is black and about the size of a 50 cent piece. anyways, this device when turned all the way toward the L and the backed off just a touch the car will run. In however, any other position, the car will start reve to 3,200 then 4-6 seconds later sputter and die with no sound of even a fire. Can anyone explain the little screw? WOULD appreciate it greatly!!!

 

on the pass side strut tower? facing the airbox? that adjusts the richness / leaness at idle. it won't have any effect at 3600rpm....

 

It changes the lean/richness of your idle. Wierd it does anything @ 3k.

 

I performed an engine swap.... ser4 87 TII just got a new ser. 5 89 engine.... done know if that makes any difference. I am still in the getting the car to run stage, It will start for untill i shut the car off if the little screw, "on the passenger side" is turned all the way toward the L then backed off about 1/16th of a turn it will run, any other spot and the car will start, the engine will automaticallly without my touching it, rev to around 3,300rpm and then lose, what seems all fuel and die.... should it run that lean at an idle????? thanx

Justin

 

You just did a S4 to S5 engine swap and you don't know what the idle adjustment is? No comment.

Anyway, I assume that you also swapped in all the S5 wiring and ECU, as well as related sensors? I am not sure that the S4 and S5 idle pots are different, but it certainly wouldn't hurt to use the one from the proper series.