I cant figure my car out. Please help!

[beansblacktsi]

well I have a 92 Plymouth laser rs with walbro 255, rc550s, aeromotive afpr, and I have a stage III key driver chip. With just the pump, fpr, and chip the car ran great just like normal. But I then installed the injectors and now the car wont idle and at about 4000 rpm in any gear it misses very bad. With the vacuum line off of the afpr the car will idle like normal and when its of its at 39psi but when reattached it drops to about 20-30psi on the afpr gauge. The car has new ngk bpr7es and wires. The car is boost leak free except the throttle body shaft which is a very small leak. And even with the stock ecu it does the same. Any help is appreciated and thanks in advanced.

 

[Tim Melton]

I dont know why it isnt idleing but it could be missing bad because you hit fuel cut.

 

[jking29]

What size of injectors is your keydriver chip set for? It sounds like it was set for stock 450 injectors and you installed 550's and are now having problems. If that is the case you need to have your chip reflashed for the larger injectors or have some other way of compensating for the larger injectors such as an afc or dsmlink.