Hey guys. Just wondering if someone here might have a little advice. I have an 85 RX with a 12A motor. It starts first try ever time, and pulls fine, but dosen't idle very well below 1500rpm. It dosen't stall below that but it's up and down the tach between 900-1200. I'm thinking it might be an exhaust prob. but I'm looking for other suggestions...anyone?

 

Vacuum leak maybe?

 

Hunting is usually a good indicator of a vacuum leak. Get a can of starting fluid and spray until you see hear the engine roar up some. Trace it down until you find the leak.

 

spray it on the vacum hose?

 

spray it around the hoses, and if you do have a leak, you'll hear the engine respond to the starting fluid. Once you have the general area nailed down, you'll be able to spray specific lines until you find the one leaking. At least that's what worked on my car.

 

Thanks alot pratch

 

I dislike using starter fluid personally since it can land on hot areas if not careful, exhaust manifold, etc, and combust easily.

I take a propane torch, unlit, but with gas on, and trace vacuum lines. A vacuum leak will suck up the propane and increase the idle without getting messy and potentially dangerous starter fluid on hot engine parts.

 

any other non flammable ways of finding vaccum leaks? Also, if the car is hunting the mix might be way off, try adjusting that first. richening mine only a tiny bit smoothed the idle right out.

 

The propane idea is great. Gets sucked in thru the leak and speeds the engine. I'm gonna try that on the 85, which still sometimes stumbles at 4000 rpm.

B