Engine Misfire in V8 mode
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Dustin Jackson
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The cam could be worn or the AFM system isn’t working properly
it's making some mechanical noise( could be a bad pulley for all i know) not like Diesel Engine though... it runs fine for the first 30 seconds with no misfire i know the hybrid might have a delay when feeding it gas
besides that is only a minor fuel injector tick which has been since i bought it,
i'll pull the belt and do a compression test on #4 tomorrow
before it started missing firing the fuel trim was 2 to 4 range which is normal range.. so a vacuum leak can be ruled out on the 11th i did an oil change i didn't see any glitter..
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so many things can cause a miss fire in these trucks. everything from a lifter eating a cam, broken valve spring, coil, even an injector getting clogged or worst stuck open. could even be a loose spark plug itself, try snuggling it down. plug itself can be bad, crack you can't even see can cause random misfires.
ground wire to the coils is down really low near the motor mount. I hadn't even seen that one before till I needed to move wires around to change a mount.
ground wire to the coils is down really low near the motor mount. I hadn't even seen that one before till I needed to move wires around to change a mount.
heavy smell of gas out of the tail pipe
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Better get it diagnosed and fixed before driving it.... You'll end up ruining your Catalytic Converters and that's real expensive !
Yes i know i'll disconnect the fuel injector for that cylinder :/
pulled the ignition coil swapped nothing changed tested the ignition coil we got spark. (just did a test from spark cable to a jumper cable to chassis ground)
most likely the AFM system broke
the fuel injector could be bad though
it runs fine for the first 30 seconds then starts shaking :/
before you unplugged the injector, did the plug come out wet or more black then the others? that could mean the injector. and unless its tapping, I don't know that it's valve train.
did you do that compression test? I don't really know how you'd do that in a hybrid without maybe a tech 2 to engage the starter.
I would go to a auto parts store, buy one brand new acdelco plug and put it in there. that it runs smooth for a bit makes me thinks it's probably spark related still.
did you do that compression test? I don't really know how you'd do that in a hybrid without maybe a tech 2 to engage the starter.
I would go to a auto parts store, buy one brand new acdelco plug and put it in there. that it runs smooth for a bit makes me thinks it's probably spark related still.
i see lots of sparks when i ground to chassis (using jumper cable) so it doesn't jump to hybrid stuff or anything else
sparking in the air is pretty easy.. you can have cracks in the porcelain or even something called carbon tracing in the plug you can't see, and when the cylinder pressure gets higher, it will jump to ground before reaching the tip to light the fuel.
just some stuff I've seen happen over the years. got a miss, basically put some plugs in it and go from there. they are disposable wear items.
I did a compression test it's only 0-3 psi So the lifter valve is stuck wide open...
if you can pull the valve cover. you might find a broken valve spring. much eaiser fix than a lifter
if it is a stuck lifter, what are you going to do? they usually tick like crazy when stuck.
mild tick
yeah it did a few time forgot to plug it in
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