Random missfire

[Schurkey]

You removed the distributor to reseal the top end.

Was the distributor ever adjusted to synch the two sensor signals?

 

[Archaic2021]

A shop did that job for ne. Its ran fine since then so im assuking thry did it. That was done last summer

 

[Archaic2021]

When the shope dine thr intske gaskets and new injectors its ran about 3k trouble free miles until now.

Sorry for the confusion

 

[Archaic2021]

I really need to invest in some proper diagnostic tools and a better scanner. I took the truck back to my mechanic to see what he sais just because I do need it this weekend if possible. I need new lights in the shop and tools and right now I have 0 time during the week.

On the 5 minute drove horrible. Felt like it was starving for fuel down low but high rpms felt better like past 2k but still had absolutely no power.

 

[SableSlayer]

Put on the new fuel filter and a new ignition coil. This is all i can see.

New plugs, wires, fuel pump.

I need ti get a gauge to read the fuel pressure but if thats good im thinking distributor?

Your long-term fuel trim should be lower than 9%. Look up how to do a smoke test with a cigar. If you can't a vacuum leak I would lean towards lower intake gasket

 

[Archaic2021]

Your long-term fuel trim should be lower than 9%. Look up how to do a smoke test with a cigar. If you can't a vacuum leak I would lean towards lower intake gasket

The lower and upper intake gaskets were done just last summer.

This issue gave no notice either it just started happening all of a sudden when from very smooth to rough very quick.


I have to ask is there anything special you have to do if you change the crank sesnor and just the crank sesnor only. I done that maybe 5 months ago but it's been running great ever since.

 

[Archaic2021]

ATTENTION EVERYONE....I AM A IDIOT lol.

I'm glad my mechanic is a friend. He called me and goes well your a DA and laughed.

When I put the new cap on, I crossed a wire...old cap was actually the issue...and I fixed it but also unfixed it at the same time.

He said it's running like a champ told me to bring him so drinks lol.

 

[Schurkey]

True random missfire.

When I put the new cap on, I crossed a wire.

Guess it wasn't a "random" misfire after all.

This is why I harp on misfire COUNTS per individual cylinder. You'd have seen this easily--two cylinders would be sky-high, and the rest probably at "0".

 

[scott2093]

ATTENTION EVERYONE....I AM A IDIOT lol.

WERE..
But even if you were charged by the mechanic,which you weren't unless his tastes are expensive, it's kinda like paying for school.. Stuff sticks a little harder for me when it costs...lol

Good job getting it sorted and thanks for the update...

 

[2000z71tahoe]

97 c1500 5.0 vortec

So just drove 90 miles home. 180 miles round trip. Get homrle and truck starts running rough. Random missfiire p0300 code.

New style style injectors
Re sealed top end
New plugs, wire and plugs
New cap.
New fuel pump
All wuthin last 3k miles

Wher should start first.

I need ti change fuel filter just havent done it

I had the same issue in my 2000 Tahoe z71 a few months ago. Was running fine then was misfiring out of two cylinders, 3 and 7. Replaced everything before, plugs wires, cap, rotor, cam sensor, crank sensor. Took to a garage told me it was injectors, so I replaced them. Same issues. So I bought a new cap and rotor and ran great. Do you have a plastic flat top distributor cap?