bad idle help
 

so I was wondering if a bad terminal on the battery could cause a poor idle.

My car idles pretty good with the jumper cables on but when I take em off it starts a rough idle. when I rev it it runs fine but stumbles on low idle.

I replaced the pos battery terminal, the battery, I took the alt to a parts store and it checked out. the only thing I can think of is the negative terminal its pretty old, i cleaned it multiple times but it still does not fit as snug as I would like.

any other ideas?

Re: bad idle help
 

What sort of voltage are you seeing at idle? I assume the alternator tested out ok?

Check all your wires. I've had power wires get corroded quite a ways up the wire so they could not deliver adequate voltage.

Otherwise the two things I always suggest checking with idle issues are boost/vacuum leaks and the idle speed controller.