i recently purchased a 1986 camaro iroc z, it has 5.0 liter stock v8,new magnaflow exhaust, but no catalytic converter, could that be a reason why it idles so high because of no 02 censor? i pushed back the throttle cable and the min rpm i can get is 1500, but if i give it some gas it raises back to 3-4k rpms, however in drive it seems to run a little higher then normal but nothing to bad. just wonder what could be casing such high idle rpms, if u can help me out id appreciate it. thanks.

 

camaro 69! help this guy already

 

take a look at the throttle to make sure that the butterflies are fully closing. if you can push it back and it drops the rpm, it sounds like something is binding and causing it to hang open. also check the throttle cable for smooth operation. there are some other possibilites, but start with the easy stuff first.

 

TPI I'm assuming?

 

Your problem might be with the IAC (Idle Air Control) Valve. Basically, it's an electric plunger with a cone shaped rubber tip at the end. It adjusts your idle by controlling an inflow of air to the TB, right before the throttle blade. To test it, remove the intake plenum tube from the throttle body. Look at the inlet bore of the TB and find the hole(s) or slot(s) in front of the throttle blade. With the engine running, hold a finger over those openings. If the idle comes down to a more normal speed, the IAC, the wiring, or the connection to it is bad. It's not uncommon for an IAC valve to go bad.

 

lol, what i did was just pull back on the pedal, an it idles at 15-1800rpms but thats the absolute minimum it will go now, probably gonna dink around with the vaccum hose and stuff.

 

if you can pull your pedal back and lower the idle then I would just replace the throttle return spring.