My tach jumps when i am crusing it deosn't really matter the speed just at constant speed and my engine also misses i just changed spark plugs, sp wires, rotor and distrib i have an 87 305 tpi. I seems to get worse with the amount of timing advance i have, which is advanced pretty far cause i put a new prom and cal pac in there. plz Help


john

 

it could possibly be a bad ignition module in the dist. sending a bad reference signal to teh computer. i think that would explain everything. Im assuming you got all new components in teh dist. so that probably isnt it but just a thought.

 

I would checkt the tach wire leading to the distributor, it prolly came a little loose when changing things.