Shut the car off( in a safe place) when the engine won't idle down, don't touch the throttle, pull the air cleaner and check to see if the choke is partly closed, also check the fast idle cam on the right side of the carb. Check throttle cable, to short or hanging up and on allowing the throttle to return?
After checking Bob's suggestions, a little carb cleaner on the choke/fast idle cam linkage will help clear any gummy substance from sitting.
How is the spring placement/tension ? Can you pull the throttle open with minimal effort ? May need to double spring it.
Thanks for the suggestions guys!
The cable was just replaced with a new one, and cleaned the linkage.
The spring is suspect looking, not sure it is even a original type.
May try Bobs idea to see what it is like when happening.
Hopefully it is as simple as the spring.
since this is apparently what it should look like.. think it is a likely fix and will try it next. the one that came with the car looks nothing like it, funny, everything else was done right by the PO
Check where the spring is attaching to the throttle place and engine also. Selecting the wrong hole on the throttle plate has a big impact on the force to close the throttle and the wrong spring angle from throttle plate to engine may let off too much spring force as the throttle closes.
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John E - Rogers, MN
Instructions? All I need is the exploded view. 70 El Camino soon to be ls1/t56 64 Malibu SS
Got the new Dorman springs for the car and it works great. Also the feel of the pedal is very solid and precise. Think I need to add to my trouble shooting list to consider if it was that way when I got the car... if it likely to be correct?
Here is what was on the car (looks a bit like a part of a screen door chain )