Need help with my distributer firing order
 

Just rebuilt my 350 from my 1977 Gmc Vandura 4x4, and noticed it wasnt running right. So while it was running, i pulled the plugs one by one from the distributor and noticed no change in engine performance on plugs 1 7 6 and 4. The distributor is producing the electrical current, but those cylinders arent firing. I did a compression test and they all are at 150. What do u think the problem is?

Re: Need help with my distributer firing order
 

make sure firing order is correct, ck for vacum leaks,may want to spray some wd40 around intake to ck for leaks. maybe some of this will help

Re: Need help with my distributer firing order
 

i've had 2 plug wires switched around and the motor run....thats what i get for having a friend help me to a tune-up... the other thing to look for is to make sure that the coil hold-down screws aren't poking through the underside of the distributor cap...cause that will cause the rotor to short out before it makes contact with the terminal right after it... course that is if your truck has an HEI dist. on it....