Ive had a holly sniper on my 66 fj40 for about 10 months now and it’s been constantly having these fits of this breathing thing where it gets really low in rpms then jumps up to high rpms and occasionally just stalling. It usually stalls when I take it out of gear and start coming to a stop where I then have to jump it by putting it in 5th gear and dumping the clutch. I was told by the guy who put the holly sniper on that it would eventually learn to not stall. I originally had it set at 720 idle and it seemed like was getting better where it wasn’t stalling nearly as much, but as it’s gotten colder it’s gotten worse so I had to set it to a higher idle speed. Anybody have any idea why it’s doing this? I guess there’s a chance it’s the fuel pump but I’m not sure. Are there specific settings on the sniper that would improve it? It gets quite embarrassing in traffic have to give it gas over and over again. It’s my daily by the way.

List of first things to fix first. Yes I’d removed the cowling to get a better look at the water pump and It seems to be idling a bit high.

1. Brake line leak
2. Water pump replacement
3. Oil pan gasket
4. Valve cover gasket