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What have I done to my precious idle??

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bricktop

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In preparation for my first car show, I got under the hood and did three things.....I swapped out a valve cover, I added some oil to the dashpots and I detailed the engine bay with some simple green and vaiuos elixirs.

Somehow I have affected my idling. What was once a strong 1000rpm rumble is now more like a rougher, weaker 700rpm shake and shimmy. Now, the carruns fine at speed, no hesitations, no sputters and no backfires, BUT when I approach a stop sign I have to engage the choke a 1/4 pull to keep it running.

What the heck did I do??

Carter
 
You've probably knocked off a vacuum line (running lean, hence the choke) or have moisture affecting the distributor cap or wires.
 
I will check and see if I have knocked off a vacuum line, but I had the hood open all day at the show and didn't see anything out of place.

I think the moisture in the dist assembly may be the chief culprit...but shouldn't that dry out pretty quickly? Particularly if the car was driven for 90 minutes afterward?

Thanks,

Carter
 
I agree with Paul. If it is not a vacuum line it is probably electrical.
Residue from the water, cleaner, or the dirt being washed off, can be left behind when the water dries. This can be conductive and cause the spark to trace a route to ground. Also, water that finds its way inside the cap can take a while to dry and work it's way out instead of condensing again inside the cap.
A good electrical cleaner and a clean soft cloth can help. But you might try pulling the plug wires and cleaning the outside of the plugs and outside of the cap first.
 
Partial loss of your points gap can also cause the idle to drop.

This can happen if the points were not sufficiently tight or because of wear on that bit that rides on the cam. In the latter case a very small dab of the appropriate lube on the cam may help prevent a recurrence.

What happens is (for whichever reason) the points gap closes up slightly and changes your timing to less advance -- doesn't show much difference at speed but will give you a lower idle.

May or may not be your problem but is the first thing I check when the idle drops for no other apparent reason.
 
carter, I just had a similar problem. I, also, had to pull the choke out some to stay running at idle. I also had just topped up the damper oil. When I removed some oil out of the rear carb things got much better. That is just my recent experience. Actually, my air valve was sticking and taking out a little oil seemed to do the trick.
 
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