car idleing high why

[marcar1993]

With motor off, remove air cleaner, plug vacuum nipple. Start motor, check what rpm fast idle is, watch as choke butterfly slowly opens. When fully open, tapping throttle should drop fast idle down to curb idle. That is what SHOULD happen. The grey wire that goes to the round black housing on the side of the carb gets 12 volts when the ignition is ON. It heats up a coil inside and that opens the choke butterfly. If it is not getting 12 volts, or intermittently, choke stays closed, and idle stays too fast.

On a stock 86 307 it would have a hot air choke, not electric.

 

[pontiacgp]

I gave the fast idle screw 3/4 of a turn to the left and it cleared it right up.

x2...if you got the carb rebuilt it usually needs a few adjustments when it's back on the engine...

 

[88hurstolds]

Check for cracked vacuum hoses, also your ILC (Idle Load Compensator) might be acting up.

 

[86_olds]

With motor off, remove air cleaner, plug vacuum nipple. Start motor, check what rpm fast idle is, watch as choke butterfly slowly opens. When fully open, tapping throttle should drop fast idle down to curb idle. That is what SHOULD happen. The grey wire that goes to the round black housing on the side of the carb gets 12 volts when the ignition is ON. It heats up a coil inside and that opens the choke butterfly. If it is not getting 12 volts, or intermittently, choke stays closed, and idle stays too fast.

thanks guys since i got it rebuilt the only thing i have adjusted is the regular idle screw will do this asap tomorrow ill keep u guys updated but that is exactly wat happens when i tap the throttle it goes back to regular idle is that how its supposed to be ? like am i good with that

 

[Bonnewagon]

They still used hot air in 86'? Damn. If that pipe is clogged or not even hooked up, the choke will act the same way. Blow through it and be sure it's clear. Verify that the motor runs fast when she first starts up, about 1500 to 2000 rpm is right. The fast idle screw is under the choke, on the pass side and only test when cold,as noted. Otherwise it works the same: as the choke draws hot air over the coil inside the black housing, it heats the spring and the choke butterfly opens. As it opens a tap on the pedal drops it down to curb idle speed. The only reason I'm harping on the choke is that unless it's working correctly, you are chasing ghosts.

 

[pontiacgp]

I was surprised also that they still used a stove pipe for the choke in 86. I guess the Olds were really the old man's car and they wanted to keep with tradition....

 

[86_olds]

They still used hot air in 86'? Damn. If that pipe is clogged or not even hooked up, the choke will act the same way. Blow through it and be sure it's clear. Verify that the motor runs fast when she first starts up, about 1500 to 2000 rpm is right. The fast idle screw is under the choke, on the pass side and only test when cold,as noted. Otherwise it works the same: as the choke draws hot air over the coil inside the black housing, it heats the spring and the choke butterfly opens. As it opens a tap on the pedal drops it down to curb idle speed. The only reason I'm harping on the choke is that unless it's working correctly, you are chasing ghosts.

right well as of now ama start working on this tomorrow but i have 2 leads as to were to start off i removed the cruise control unit 2 months ago and i need to recheck and replug the vacumm lines that went to it i dont know if this has to do anything with carb but yeah
ALSOi totally forgot about this sorry guys but this might be the factor after all am still not sure the vacumm unit that is located right underneath the passenger side header panel it looks like a ball with 2 lines going in one is vacumm that comes from the top of intake and idk what the other one is but both of those hoses are original so they are all smushy and arent even connected and havent been for a while since i havent had any cash but tommorow and going to relocate that unit hook up some new hose we will see if that fixes it and since am on this subject am just going to ahead and replace most of the vacumm lines that seem smushy i hate this era or engine its freaking maze as soon as u open the hood u get lost trying to find the engine but have to work with what i got for now

 

[Bonnewagon]

Yes, do fix all vacuum leaks then see what's up.