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Discussion Starter #1
My 84 used to idle right at 800 RPMs, every time. It would never stall, unless it was super cold out and I tried to drive away without warming it up.

Now it's doing something really weird.

I started it the other day to drive to class, and after it had warmed up a bit w/ the choke @ 2k rpms, I tapped the gas and it dropped to <500 (I'd say between 200-400 RPMs). Then it stalled because it was idling so low.

To restart it, I had to hold the pedal WOT and crank. It started right up and idled low, so I pulled over, adjusted the idle screw by hand and put it to about 800 RPMs again.

The car idled rough still (though higher), but under power the car has no missing and pulls great.

Think it's a vaccuum leak? I can't figure out what else would cause this... so I just keep turning the idle up.
 

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Discussion Starter #2
ttt
 

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I'll bet it is a vacuum leak. My '83 did the same thing. I found that one of the rubber vacuum lines had cracked. (18 years old).
Good Luck!!
Chas Randolph
 

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Mine was doing that last year and I didn't know why. I switched alot of stuff this winter and gave some of my old crap away. My buddy took my fuel pump and put it on his car, lo and behold that was the problem, that caused all my headaches, I felt like a moron...It was only putting out about 4psi. He took it all appart an cleaned it, now it works great. Good luck!
 

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Dan said:
To restart it, I had to hold the pedal WOT and crank.
This suggests that its flooded, or at least very rich. One common thing to happen to a Holley is for a bit of trash to get in the secondary side needle-and-seat. This holds the needle off the seat and fuel continues to flow into the secondary float bowl even though its full. The excess runs into the engine.

This happens to the secondary because there is very little fuel flow unless you're at WOT. And on a stocker there's not much even then when compared to the primary side. Cars with Holley's that don't see much in the way of WOT operation suffer this alot. Anyway one possible way to improve matters is to go out and in a safe place and run the thing WOT through the top of Third. If you've got highway gears then the top of Second might do. If after the first pass it doesn't improve, then try another. If it doesn't improve after that then you're gonna need some carb work (or at least inspect the needle-and-seat assemblys). It would take a while to do a step by step description so try the "Italian Tune-Up" described above (ie. run the piss out of it :) ) and if you need more help get back with us.
 
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