Hi everyone.

I have an 87 Iroc 305 tpi. It has a cam in it and a hypertech chip. The problem is I can't get my idle down from 1500 rpms. My mechanic has been trying to fix it for days now and I figured I would post something here for additional input. The idle came down for him when he changed the timing, but when he turned the motor off then back on again, it went back up to 1500. Right now he and I are trying to troubleshoot the problem by putting the stock chip back in. Also I've added edilbrock headers and a borla exhaust. The engine is running poorly in general. It has a 4:10 rear which should be ripping up the pavement, but it's not. Thanks in advance for any advice.

Josh

 

Try checking the line that goes to the vapor canister, if not the clip that attaches it. Most of 'em do have a cam BTW.

 

Thanks a lot, I'll see if that helps and I'll let you know. I bought the car a few weeks ago and have been trying to get all the kinks worked out of it.

 

Moving to TPI board.

 

After you check the EVAP purge line, also check the PCV valve and hose, TPS voltage, throttle stop screw, power brake booster for leakage, EGR valve for leakage, usual gasket leaks, and IAC valve for sticking.

 

Do you get a check engine light? If you do, check the coolant temp sensor, my camaro had a very similar problem and that's what it turned out to be.