[AdamHoud]

I have a strange problem that occured twice in the last week. After driving the car normally, it will sometimes get stuck in a really high idle that will not go down by tapping the gas pedal. I have found that if I pull over and turn the car off, and restart it, it runs just fine and idles low. This makes me think it is something to do with the electric choke perhaps? Any suggestions?

[smagnotti]

A 73 bird doea not have a electric choke, so what carb do you have?

[AdamHoud]

My 73 bird has an electric choke. I have a late 70's qjet professionally rebuilt.

[Stuckinda60s]

Pull the carb, drain it and, looking at the throttle plates, push the throttle bellcrank all the way toward the stop looking for marks where the plates may be hitting the throttle bores. Then, check the alignment of the throttle plates and rotate the throttle all the way to full open and let it return, every time checking to make certain it returns to the fully-closed position with the screw all the way against the hot idle position on the cam, without having to push it to rest.

The plates may have been removed when the carb was rebuilt and are touching the bores, not letting the engine idle down. Professionally rebuilt doesn't mean the same if it was done by Sammy Shadetree as it would if it was done by someone like Cliff. Even when done by a specialist, the possibility's there for interference when the carb heats up.

[AdamHoud]

I will have to look at it later, I wasn't able to make it happen again yesterday. By professionally rebuilt I mean Jeff Walker, because Cliff has too long of a wait list and Jeff does excellent work.

One thing to note is that I just realized this problem occured AFTER adjusting the idle speed, because prior to that it was idling too low/rough.

[twisted]

A little less safe route, but couldn't you wait until it does it again, pull over throw it in park, and look down the venturi? and see where the plates are sitting? At idle they should only be slightly open.
With an electric choke, is it possible that it is getting feed from something powering it? poorly routed cracked sparkplug wire? Or is that just a bad theory?

[twisted]

Originally Posted by AdamHoud

I will have to look at it later, I wasn't able to make it happen again yesterday. By professionally rebuilt I mean Jeff Walker, because Cliff has too long of a wait list and Jeff does excellent work.

One thing to note is that I just realized this problem occured AFTER adjusting the idle speed, because prior to that it was idling too low/rough.

Possible something like dirt from the tank got into it and reduced your flow? When you adjusted your idle opening it up more, it broke loose, and now there is too much flow?

I am full of hypothetical crap today!

[smagnotti]

If you adjusted the idle speed with out re-adjusting the high idle screw, then thats your problem right there. When things get hot enough and expand probibly even .003" to .005" to much the cam high idle cam hangs up.

[roadrage david]

i had something simulair ones with my gto .
it started out like that and i kinda ignored it till i chalenged some rice burner cracker jack toys on the boulevar overhere .
i made a burnout and shot away ,only for my engine running at full trottle afther i took my foot of the gas. it scared the hell out of me!!!!!!!!!!. i braked as hard as i could and in my panic at first never tought of turning of the contact, with i finaly did. when the end of the road and the river came closer .
we founf out there was a serius ressin build up in the carb that made this happen .it lookt like a very thin layer of clear coat ....

[AdamHoud]

Weird....The whole carb was adjusted after tweaking with the idle speed. The carb was freshly assembled/cleaned when Jeff built it for me. I did however run some older gas through it mixed with newer gas/additive after getting the engine all back together.