debock04

Hi everyone,

My name is Tim I am new to the forum. I have a 1979 ford f-150 with a 351 motor. my question is. Is my truck misfiring or what? it is hard to keep running, once it gets warm it will stay running but almost dies every few seconds. I have checked all the plugs and wires. when I had it running I pulled one wire off at a time to see if I could find which cylinder it was and I think it is number 2. So I replaced the plug and still did not fix the problem. Also is sounds to be knocking at higher RPM’s. Any ideas?

Thanks

debock04

any ideas?

Good old Bill

Don't think a single cylinder with cause the engine to die. Have seen to many engines with a dead hole and still are running. Being an older vintage, its most likely a carburation problem. Check your vacuum at idle, what is the reading and is it steady. Next, remove the EGR and block off with a piece of cardboard for a test, do not leave in place permanently. Am loosing the symptoms, explain in more detail. Again ignition woes isolated to a single cylinder isn't your problem, need to affect the engine as a whole.

Strangerous

How's the gap on those plugs?

debock04

thanks guys for the info, "good old bill", the truck is having a hard time running at idle sometimes it dies. on the EGR valve, your sayin to cover the valve or the hole on the oil cap? or both? also if it is the carb what is the fix? "strangerous" i gaped the new plugs to spec. .044
once again thanks for the help and i hope yall have more to give!

basssteakman

check the power valve in the carb. If it backfired it can blow out the power valve and cause the engine to run so rich that it's unstable.