Slowpoint0

when i start cold it idles around 1,300 then slowly sneaks up to 1,700 after warmed i (blip) the gas and the idle goes up to 2,000 rpms if i punch it it still sits at 2,000.
i noticed the idle screw on drivers side doesnt contact its stop, like something is stopping it from going down.

from reading other posts this is what i'v tried. I'v sent car in to have it timed. when i got it back it still rose into high rpms, they said it had vac leaks,so i checked for vacuum leaks, found one small hose leaking, replaced it and still no better.

iv read that the wire to chock could be bad?? or low current? i dont understand what the tool is to check for that?


i love to hate this car..

camarito

or maybe it's adjusted too high

BLT

Warm the car up and take the air cleaner off. The choke plate should be 100% open. Also look down at the throttle butterflies and make sure they are closed. Is the throttle cable not allowing it to return fully?

Or like camarito said, its likely its adjusted too high. Look up your carburetor online and find the base idle setting. Count what yours is. I have a holley 1850 and my idle screws are 1 1/2 turns out each. Any less and the RPM is too high (which you would think is opposite, but I guess thats why there is adjustment screws for each vehicle)

It could be a gasket on the carb or manifold, or a vacuum leak. With the engine running you could lightly spray carb cleaner around the vacuum lines and gaskets, if the RPMS change then air is entering somewhere its not supposed to. My PCV gasket was worn last year and was causing a leak when it was warmed up.

Slowpoint0

I will look up adjustments. Iv never adjusted or had it adjusted since iv owned it, ran good before!
Choke is open 100% and butterflies are closed.
Can't find any more vac leaks. Sprayed carb and traced all vac lines and sprayed manifold no change in idle

Apeiron

Check for +12v on the choke wire. Don't mess with any screws.

Slowpoint0

Ok have 12v to choke, after checking I left car alone. Came back hour later started it and it runs fine. Could choke wire have just been loose??

naf

iTrader: (7)

Yes. If it's idling high and not resting on the curb idle screw, it's likely being held up by the fast idle cam under the choke. It's purpose is to allow the idle speed to be increased while the engine warms up (as the choke opens). When the choke is completely open the throttle will still rest on the fast idle cam until the throttle is opened enough to lift it off so it falls away (gander at it and you can see how it's supposed to work). If it doesn't fall off (and rest on the curb idle set screw) the choke's either not opening or the linkage is gummed up. Sometimes it's a good idea to spray the linkage down with some carb cleaner.

Slowpoint0

When it was idling high all warmed up the there was like 1/8" between the curb idle screw and it's stop. I could push the linkage so the idle screw touched, but it was real hard to move. And it would idle right back up high soon as I let it go! I cleaned carb with spray cleaner it did not move any eaiser.
But it's running fine now.
Maybe I'll have carb rebuilt? Get everything adjusted/cleaned right, and tune it.

naf

iTrader: (7)

The exact behavior one would expect when it's resting on the fast idle cam with the choke engaged or before the throttle has been blipped to drop it off. Observe the (usually) green lever under the choke stat and how it's weighted on one end so it drops away when the choke is open.

Slowpoint0

The problem was after warm up I'd blip it and it wouldn't let go down. It would idle real high and sometimes when I'd shut it off. It would bog/sputter run without the key on.

I'll look at the linkage. They are green rods!

naf

iTrader: (7)

Green is the teflon coating on them, to help keep them from sticking.

Slowpoint0

turns out there was a small wear spot on the wire to the choke that was arcing out. when i tested it for 12v i lifted the wire up. i moved the why today and it idled right back up i repaired the wire and car runs great..

hope it stays..

thanks for the help..