I agree if it was cam related there would be random misfires in all cylinders. If you have access to a scanner that reads live misfires, see if it's racking up misfires at cruise speeds too.
If it is only #7, then I'd look there. Any chance that one of the rockers slipped off the pedestal or a pushrod came out, or a broken valve spring? There is also a GM PIP regarding misfire code after engine repairs traced to injector harness accidentally swapped (I posted the wire colors earlier in this thread).
Is there anything at the back of the intake that could have fallen out? PCV hose, one of the manifold plugs, booster hose got torn, etc? If you listen to the injectors with a stethoscope or a piece of tubing, do they all make the same clicking sound?
6.0 p300
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Schurkey
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Re: 6.0 p300
P0300?
WHAT SCAN TOOL? If it's a cheap "consumer grade" scan tool, you might be getting incorrect information. Shitty scan tools ignore the "real" code, but only display the generic code instead. In this case, you're being told it's a "random" misfire, but the real code could be cylinder-specific.
As said, you need to look at the misfire reports cylinder-by-cylinder; and it would be useful to just inspect the entire data stream for anomolies.
WHAT SCAN TOOL? If it's a cheap "consumer grade" scan tool, you might be getting incorrect information. Shitty scan tools ignore the "real" code, but only display the generic code instead. In this case, you're being told it's a "random" misfire, but the real code could be cylinder-specific.
As said, you need to look at the misfire reports cylinder-by-cylinder; and it would be useful to just inspect the entire data stream for anomolies.
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midnightbluS10
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Re: 6.0 p300
Have you ruled out the injector(s) themselves?
JC -
bigjoe1 wrote:By the way, I had a long talk with Harold(Brookshire) last year at the PRI show. We met at the airport and he told me everything he knew about everything.It was a nice visit. JOE SHERMAN RACING
Re: 6.0 p300
Altel MaxiSys is the scan tool.
I haven't touched the fuel injectors yet. Trying to stick with what I could have messed up swapping out the cam.
As far as the missing it seams random just seams to miss the most on 7 then 4 then seams to balance out...However its always at idle. Its been suggested to measure the cam and see where numbers fall as far as center line numbers. I will double for vacuum leaks.
I haven't touched the fuel injectors yet. Trying to stick with what I could have messed up swapping out the cam.
As far as the missing it seams random just seams to miss the most on 7 then 4 then seams to balance out...However its always at idle. Its been suggested to measure the cam and see where numbers fall as far as center line numbers. I will double for vacuum leaks.