Hey folks,
Well, I got rid of the old gas sucking 770 and put on a holley 600 (electric choke/vacuum secondaries) last weekend. Things were working great for the first few days. Idle in gear was at a steady 600.
Yesterday, I was in some serious stop and go traffic downtown on a really hot day and when I finally got home, I put her into park, and the idle starts fluctuating, going from 550 to 650 and back down again over and over.
And its only when she is in park, in drive it doesn't fluctuate at all.
Although when I took her out again, when the engine was still hot, she nearly stalled making a left turn!
Is it a vacuum leak maybe? It only occurs when the engine is hot.
Also, if you pull off the choke cap all the way, does that totally disconnect the choke? As I did just that, and the butterfly sprang fully upen. Maybe that has something to do with it? Anyways, any help with this would be greatly appreciated! Cheers

Sean

My vote would be an air leak.....happened on my truck same way pcv valve came out of the valve cover...ran like crap....plugged it in perfect.

Hey folks,
Also, if you pull off the choke cap all the way, does that totally disconnect the choke? As I did just that, and the butterfly sprang fully upen. Maybe that has something to do with it? Anyways, any help with this would be greatly appreciated! Cheers

Sean

Yes, that kind of messes up the choke when you pull the cap off. That's a bi-metal thermostat spring that heats and releases tension (opens the choke) when electricity is applied. The cap holds a certain amount of pre-tension and can be adjusted clock/counter clockwise to adjust tension. I don't know how much tension it needs, may be someone will chime in with that info.