2003 Tahoe 5.7 running issues
- Thread starter Boruble
- Start date
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have you checked out the fuel pump control module? maybe the harness is corroded? just something to check if you haven't yet, I would also hook up a fuel pressure gauge to see what is happening when the problem occurs also, you can get one cheap from harbor freight, ebay, amazon. Pretty sure the transmission would have nothing to do with the problem even if it was completely fubar.
HiHoeSilver
Away!
Is the security light on?
Probably not unless it just starts and dies almost instantly, then it wouldn't just decide to start later all on it's own you would have to do the relearn every time it happened and the security light would be flashing at you as well like Nate said. sounds more like a fuel issue to me
SnowDrifter
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Hey stupid question here but could you clarify the engine size? Just want to verify if it's a typo or if you have a different engine swapped in. Pretty different diagnostic trees for each
If it's the 4.8/5.3/6.0, lets draw a big ass dividing line here between general fueling issues and all parts within that system, and everything else.
Grab several cans of ether from the store. When it acts up, can you force the thing to run on starting fluid?
If yes, check fuel pressure. I know, new fuel pump, check it anyway. Would be too long to type in the rest od the steps here on mobile so start with this and post back.
If no, check for spark. If you do have spark, check for ignition timing via scan tool.
Post results and we'll go from there. Would be entirely unruly and confusing to type out an entire diagnostic tree and all the minutia that goes with. So we'll take this one step by step.
Oh yeah, and do you have any codes? Stored, pending, current, and confirmed. I want to know them aaaaaaalllllllll
If it's the 4.8/5.3/6.0, lets draw a big ass dividing line here between general fueling issues and all parts within that system, and everything else.
Grab several cans of ether from the store. When it acts up, can you force the thing to run on starting fluid?
If yes, check fuel pressure. I know, new fuel pump, check it anyway. Would be too long to type in the rest od the steps here on mobile so start with this and post back.
If no, check for spark. If you do have spark, check for ignition timing via scan tool.
Post results and we'll go from there. Would be entirely unruly and confusing to type out an entire diagnostic tree and all the minutia that goes with. So we'll take this one step by step.
Oh yeah, and do you have any codes? Stored, pending, current, and confirmed. I want to know them aaaaaaalllllllll
SnowDrifter
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Also before I forget, does 03 have a return less fuel system? Or does it have the vaccuum modulated fuel pressure regulator? Pop the vaccuum line off the thing and verify raw fuel isn't leaking past internally.GGive the exhaust a few whiffs too. Just general smell. Don't go putting your face in the tailpipe like you're trying to snort a line of some illicit product off a ******'s *******
