Ggg
Registered User
I do not work on gas engines very much but I had to in this case. Truck is a 91 GMC Top Kick with a 366 Big Block. I am having some issues with it. It idles a little rough, revs up just fine without a load, but when driving it the engine does not want to rev up, and it will back fire up the intake. I am having a hard time finding a manual for medium duty trucks so I can set the timing, what is it supposed to be?
