Dead miss

Just replaced just about everything on my pick-up. Rebuilt heads, new injectors, new plugs and new wires, egr valve, ects. It has a dead miss with all plus firing and I can’t seem to locate the source. Help!

It"s a 1996 Chev. pick-up with a 350 motor.



Since all plugs are firing it would seem to be a gas issue. More info would be helpful, some thoughts are clogged pickup sock in tank, bad fuel filter, bad fuel pump. There are ways to check before replacing so ask!

A dead miss with all plugs firing means either a fuel delivery problem to one cylinder or more or a compression problem…like a bad valve.

Check the fuel line pressure and test the fuel pressure regulator.

Also check the vacuum. If the needle is not stable, check the compression on each cylinder.

Post back with the results.

Isolate the dead cylinder. Run a compression test on it. If you have spark and compression, then you must have a “dead” injector…

Scanning for codes as a start might help.

Does this miss exist only at idle or is it felt when the RPMS are up also?

My truck has rebuilt heads, factory rebuilt, new injectors, plugs, and plug wires. It misses when idling, rev it up and it stops missing. Still puzzled.

You have to check the basics.

Check for codes
Check for missing spark on each cylinder.
Check the vacuum (a wobbly needle is a sign of a vacuum issue either via the valves or leakage)
Check for even compression
Check the fuel pressure and its stability (as in fuel pressure regulator).

When you’ve checked these things, post back and we’ll help from there. Until you do, there’s not much more we can offer.