|
Re: diagnosing this fuel/spark issue
I'd guess you have a vacuum leak. Try plugging off your vacuum ports one by one to isolate where. Distributor vacuum advance diaphragm might be shot.
Two screws on the Rochester are idle speed adjust and idle mixture control. You can do a rough adjust on the mixture by turning clockwise until it stops, then 1.5 turns ccw, but the truck needs to be idling in order to set it correctly - if you haven't touched the mixture adjust and it ran right in the past - leave it be. Otherwise you'll just add to your mystery.
|