New user new idle problem

[stevo911]

Hello,
Just bought a 91 rs laser from a friend of mine who stated alternator was shot and he was having a problem idling. I got the alternator replaced but am having some problems with this idle. I was a jbody tuner so going to dsms was a bit of a change. The problem im having is a high low idle itll go anywhere from 12-1500 one start and others go from 500-800 nothing really seems to change this just depends on what it wants to do at start. Not receiving any engine light on idle. Two things I noticed this car seems to be able to rev past 4500 sometimes and sometimes it wont at all just kinda bucks but rpms do not drop. When this does happen the engine light goes on and then goes off when the pedal is released. Also when driving at a cruising speed where my foot is on the gas but not really pressing down just to keep a steady speed it bucks some more. Now the z24 I had would do this due to a fauly egr so I took the vacum line off and caped it and still having same issue. I am reading the fourms here and it all seems to be BISS IAC or TPS. I tested the TPS and it is working ok. The BISS I checked and o ring is there and still tight and without the car moving to different altitude I dont see why it should be adjusted. The IAC I am wondering if this can still cause an issue shouldnt this shut off when the vehicle is put into gear and the TPS lets the ECU know the throttle is being moved? Basically what I am asking is if anyone else had this problem and what resolved it.
Thanks for your time.
And any help greatly appreciated.
Steve

 

[hubz91talontsi]

My car does the same thing. Does this only happen when you car is warmed up? The problem is you need a new throttle body.

 

[stevo911]

Its a little worse as I heat up. Will try a throttle body soon as I can get to the scrapyard and pick one up.
Should also state that everything is stock nothing changed

 

[stevo911]

Not sure if this is related but my cruise control is dead also. Wont keep a steady speed or accelerate.

 

[Grescht]

sounds like an electrical problem. Check your IAC. That could be messing up. Make sure you check it when the car is warm though. Do you have good vacuum? check your MAF make sure none of the wires are messed up. That could be putting you in a limp mode. and cruise.... hmm maybe speed sensor? see what kinds of codes your throwing? If the light is cutting on the ECU probably saved the code. Get it checked out.