missing under load, backfires, popping
05-23-2011, 02:37 PM
#44
Notorious BIG
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UPDATE: Injectors are back from FIC and just as expected, they were in perfect working order. I spent the $89 and had them completely rebuilt anyways just to be 100% safe. I'm sure it was probably a waste of money though.
I did get a new MAP sensor and fuel filter from Torque_Wrench and i'll be putting it all back together soon as time permits. probably won't be for another week or two.
AKlowriderz71 - I hear ya man and i so much appreciate the post trying to help me out. I just don't see how it could possibly be wires or spark plugs, i've changed them now twice, and since i broke one plug taking it out, i'm going to put another brand new set in when i put it back together again this time.
I did get a new MAP sensor and fuel filter from Torque_Wrench and i'll be putting it all back together soon as time permits. probably won't be for another week or two.
AKlowriderz71 - I hear ya man and i so much appreciate the post trying to help me out. I just don't see how it could possibly be wires or spark plugs, i've changed them now twice, and since i broke one plug taking it out, i'm going to put another brand new set in when i put it back together again this time.
05-23-2011, 09:31 PM
#45
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My brother's 2000 chevy pickup with a 6.0L liter had these same symptoms, finally fixed it when we swaped the ECM. He had something welded on the pickup without disconnecting battery and i'm sure that's what made the ECM fail.
05-24-2011, 10:22 AM
#46
Notorious BIG
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Nothing has been welded recently but there has been several things in the past welded to the frame without the battery being disconnected. Wideband 02 bungs, mounting brackets for my heat exchanger, thats all i can think of at the moment.
06-13-2011, 05:06 PM
#47
Notorious BIG
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UPDATE:
changed out the PCM, still not changes, still missing
To recap:
Truck misses under almost all circumstances....very small hint of a misfire during idle after truck is up to temp.
Misses under light load after up to temp
Misses under moderate load (60% tps) at all temps
HpTuners log shows 0 KR, no misfires, no codes, no CEL
No check engine light (and it does work)
changed plug wires twice
changed plugs 3 times
changed coil packs
injectors
O2's
checked for broken valve springs
leak down test
compression test
Someone please just steal this ******* thing
changed out the PCM, still not changes, still missing
To recap:
Truck misses under almost all circumstances....very small hint of a misfire during idle after truck is up to temp.
Misses under light load after up to temp
Misses under moderate load (60% tps) at all temps
HpTuners log shows 0 KR, no misfires, no codes, no CEL
No check engine light (and it does work)
changed plug wires twice
changed plugs 3 times
changed coil packs
injectors
O2's
checked for broken valve springs
leak down test
compression test
Someone please just steal this ******* thing
06-13-2011, 05:45 PM
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Have you checked the fuel pressure? Have you tried to disconect 1 plug wire at a time to look for the bad cylinder, or do you know for sure it jumps around? With it idling have you sprayed ether in the engine bay to check for vacuume leaks?