My truck is misfiring in cyl #4. It randomly fires maybe 50% of the time better at half throttle, extremely bad at 1/4 throttle. Only on cyl #4. It has been doing it for a while so I replaced all plugs and wires. Didn't help, so I replaced the #4 coil, this didn't help either. Any thoughts? It is a 2000 5.3 silverado. Thanks

Ryan

 

Burning oil? How did the plug look when you took it out compared to the rest? What other mods do you have? Ever run nitrous?

 

#4 injector could be clogged up?

 

no stock work truck, about 60000 miles, no mods, plug was wet and black, it definitely wasn't firing

My problem is definitely not with the injector plug or wire

I have tried multiple wires and coils, I definitely have a wiring or computer problem. But nothing has ever been apart and is all stock.

Thanks

 

Definitely getting gas. Thanks

 

injector stuck open? might try swapping it to another cylinder and see if it follows. driver for that cylinders injector/coil failing? does it do it when it warms up or no particular time?

 

Does it all the time.

Would a stuck injector cause a coil not to fire? I mean I used a timing light on the wire and there is not spark about 50% of the time.

Thanks