Ignition/Vacuum or what?

[Kimbrough]

My 1988 GW idles rough. I've been trying to track it down for a while. It has a AMC 360 2v motor. I did hook a vacuum guage to manifold vacuum ports - it reads @ 17? HG but fluctuates rapidly (wiggles) between 18? and 15?. Any ideas?
The book sez this either points at leaking valves or ignition.
Timing checks out fine. New EGR valve. Vac hoses all look good.

[wagdriver]

Sounds like you have got a vacuum leak some where. Take some carb cleaner and spray aroung the base of the carb and vacuum connections. When the idle smooth's out you have found the leak.

[la mula pescadora]

just be careful with that carb. cleaer since it is extreamly flamable

[bchesley]

Take the vacuum pump and check all the vacuum driven accessories. I found a leak in my charcoal canister that was causing my rough idle.

[redneckd out]

Hey again! Unfortunately, the fluctuation makes the idle problem sound more to me like compression leakage at the valves or valve guides! Have you checked compression at the spark plug holes? We got an old guage if you need one. CR

[Kimbrough]

===UPDATE===
I checked the purge valve on top of the charcoal canister - ITS BAD!!! This could be IT! Also, hoses were mis-routed. I fixed those and throttle response seems better - we'll see...

Blake - let's go wheelin!!! tongue.gif