gavinho

Truck is missing and lights the SES. Code for 'misfire in cylinder #1' keeps reoccuring. Have replaced coil on #1, all plugs and all plug wires. Any thoughts?

MT-2500

What engine and mileage?
Does it have good hot blue spark to plug?
Double check spark plug or switch with another one?
Got compression?
Check injector plug in wiring and for injector pulse.

__________________
Remember proper testing gives us the answer to many problems.
MT

gavinho

5.3L with 44,000 miles. Plug looked good, but have yet to check spark. Carbon build up in throttle body?

MT-2500

Check for good spark and switch plug and or coil /wire with another one and see if miss moves to another cylinder.

__________________
Remember proper testing gives us the answer to many problems.
MT

gavinho

Good spark, had codes erased, didn't make it out of parking lot before SES came back on. How can a shade tree check injector?

MT-2500

If good spark and plug good and good compression.
First check on a injector would for injector pulse with a injector noid light.
If good injector pulse the best shade tree is to test switch injector with another cylinder and see if miss follows injector.

__________________
Remember proper testing gives us the answer to many problems.
MT

gavinho

Thanks MT, I'll give it a shot!

MT-2500

Good luck and let us know how it goes.
PS
I have found some where the coil and or injector plug in was not making good connection. Try unplugging and plugging them back on to.

__________________
Remember proper testing gives us the answer to many problems.
MT

gavinho

#1 injector replaced (by a pro) and problem seems to be fixed at higher revs, but still idles poorly. He thinks poor idle is due to the bottle of injector cleaner clogging fuel filter? Will change the fuel filter. Are we into vacuum leaks? Yikes!

MT-2500

Good luck.
Also check egr valve if a bad idle.
Good luck and let us know how it goes.

__________________
Remember proper testing gives us the answer to many problems.
MT