Thread: idle won't calm down!

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I have this 327, all stock, that won't idle down when I take it out of gear.. ?? any thoughts on why?

whats it in? what linkage? carb? Somthing has to be a little bound. can you bring it down by haND??

It's in a 67 Caprice Coupe. 4bbl carb. Was acting just fine yesterday- I'd put it in Park, it'd idle up for a sec then calm to norm. now it won't relax. I'll go look to see if there's a fallen leaf caught up in the linkage.. as far as bringing it down by hand goes- sure, but, I'm not so sure I want to f with that since it was peachy yesterday.. : /

no leaf. all clear. nothing looks bound.

"has" to be bound? - nothing else would cause this?

Is your return spring in place and functioning? How about vacuum lines? Having one off will drive your idle speed way up. If it was fine yesterday and started suddenly you're likely looking for some mechanical/physical change that happened.

with the engine OFF, remove the air cleaner and move the linkage to WOT then let it back slow. see where it hangs up. There has to be somthing making it not return. Vac line as Roger said realy would be the thing to look for.. May be off trans in automatic. could be check valve on brake booster if you have power brakes..you just have to look.

Do you have an idle stop solenoid? If so, it could be bad or came un adjusted.

Secondaries sticking open a bit?

rs makes a good point...........you could have a cracked vacuum hose. It may look ok but could be dry rotted and cracked.

this same thing happened to me. it was a vac hose cracked.it looked ok but had a split in it. yep, the prolem started all of a sudden just like yours. all the hoses and vac lines on my car are old. really, i should replace everyone of em.

Yep - over the winter I replaced the dist advance hose, (along with the rest of them) on my '31 - only a couple years old, but split on the bottom, possibly from a couple very heavy backfires that also filled my carb full of crud (put the dist in way out of time).

A quick way to isolate a leak like that would be to locate the vacuum port remove the line or lines, cap the port and see if that changes your idle problem. Leave the vacuum line connected for the distributor advance. Your vacuum advance I would look there also.

67 Caprice, not sure but if it has vacuum controls for the AC & heat that could be a dicy little problem. Capping the vacuum port after removing the vacuum lines, except for the advance would isolate all of that also.