Idle Not constant

[steveko]

Hey has anyone had this problem the idle will stick after the car is warm but only when I shut the car off for a little. Motor still at operating temp. Usually about 200 to 300 above 1000rpms. Then drive a little ways then it will return to normal.

[A20A1]

Check coolant level, could be a thermovalve, or problem with the fast idle unloader.

[steveko]

Thanks for getting back to this question I wonder if it has anything to do with the flatspot I have at about 2000rpms and the plugs being whitish as I stated in the other post? I have checked and set the Fast idle unloader. It could be as you say coolant related or the Thermovalve although the coolant is fine at operating temp at the radiator. I will say this it still even though it 70 - 75 deg out takes like 3-4min to warm to operating temp and the RPMS too drop from 2000 to 900-1000.

[A20A1]

it could be the fast idle cam resetting, it has stages to it. So maybe it moved back a notch and upped the idle but since you were already warmed up it went down fairly quickly.

[steveko]

What about the flatspot at about 2000rpm in gear when accelerating?

Steveko.

[Hans]

My engine sometimes will start off with a slightly higher idle but after like 5 min will return to normal. Idk about yours though

[A20A1]

What about the flatspot at about 2000rpm in gear when accelerating?
Steveko.


Flat spot could be from dirty fuel system, weak fuel sytem, bad accelerator pump on the carb, electrical problem like loose wires or dirty connections, bad ignition / spark or improper timing. Also could be a vacuum leak.

[steveko]

Although I've replaced most everything mentioned new fuel,filters fuelpump,plugs wires cap. I have yet to check the timing advaced seems too start fine. If that means anything. Fuel pressure questionable reads 2.5 PSI on check with relay out and jumper in place and key on. Ijust can't locate any vaccum leaks at this time.
___________
Steveko

[steveko]

I forgot to mention the acceleratorpump was set to book factory specs as far as pump arm travel. seems to squirt in fuel with engine off looking in carb bore. I'm wondering if I should have replaced the whole friggin carb might be easier with all the stuff I've replaced on that thing.

[A20A1]

You could also check Compression in the cylinders.

[steveko]

Good point I don't know why I've been putting it off mabey because the car has too be at operating temp and throttle wide open when cranking while all the plugs are out.,for easier cranking and save the battery a little.

Probably just laziness.

[synikil]

Check the fuel pump pickup screen again.. You might have crap in your tank and even though you change your filters and pump the pumps pickup screen will clog up easily in as little as a 1/2 tank of gas causing the car to run rough again. When the car isn't running the fuel pump will allow the crap to fall away from the screen but after its been running again for a few minutes I think it could cause it to clog up again.

[Tomisimo]

It sems like alot of oss have a problem with idle. I do to.
Whi we dont make one Sticker about thet?

[steveko]

Yeah, that sums it up at least with my car being carborated and ten thousand vaccum lines .Also answer to Synikil's possibile dirty fuel tank It had been flushed out last summer with new full tank of fuel 93 octane not that the octane matters much.Didn't change then either the problem that is.

[steveko]

Hey today and the last couple of days the idle would creep up on it's own 200-300rpms above 900-1000rpms not only when I shut it off and go in a store for about 10 mins. Also,when leaving work after it's warm temperature is hotter out I will say this 85-90deg. When accelerating it will stick when I am stopped at at a stop light., I'll tap the trottle lightly,to get it to drop slightly.But then, when I take off from another stop light. It will happen again and so on and so on. Now what do yah think this could be?

[steveko]

It seems like what A20A1 said. but,when it gets hot the fast idle cam resets itself but when its cooler it will stay at about 1000rpms.and won't reset itself sounds like only when it gets really hot.For some reason or other.:huh: