'02 suburban, fueling/running issue
09-02-2014, 11:25 PM
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'02 suburban, fueling/running issue Running rough, barely goes 30mph.
Only pulling 40psi at the rail. If we disconnected vac from the regulator pressure went up to 50psi. system did not hold pressure after shutting the motor off. There was no fuel in or around the regulator.
Checked fuse and relay, both good, New filter this morning.
We're told this narrows it down to the fuel pump.
So we dropped the tank and replaced the fuel pump.
Upon reinstallation pressure with new pump was bumped to 45psi, drawing 12 amps now as oppose to 9.2, and nothing else has changed. Pressure still drops with rev. Still runs like hell, barely idles.
Pulling codes PO101 and PO300. We're assuming MAF now but what else could it be?
( more information here http://www.reddit.com/r/MechanicAdvi...anks_to_start/ )
Only pulling 40psi at the rail. If we disconnected vac from the regulator pressure went up to 50psi. system did not hold pressure after shutting the motor off. There was no fuel in or around the regulator.
Checked fuse and relay, both good, New filter this morning.
We're told this narrows it down to the fuel pump.
So we dropped the tank and replaced the fuel pump.
Upon reinstallation pressure with new pump was bumped to 45psi, drawing 12 amps now as oppose to 9.2, and nothing else has changed. Pressure still drops with rev. Still runs like hell, barely idles.
Pulling codes PO101 and PO300. We're assuming MAF now but what else could it be?
( more information here http://www.reddit.com/r/MechanicAdvi...anks_to_start/ )
09-06-2014, 08:52 AM
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im having basically this same issue with my 03 6.0 it will start up but bogs down real bad not getting enough fuel. checked regulator also and no fuel in or around the vacuum and new fuel pump still not getting enough fuel for some reason
09-06-2014, 09:02 AM
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Their fuel pump was going bad and not holding pressure, which was causing hard starts and lean conditions right at the start. Then their MAF went out and they drove 160 miles with it running very rich. After replacing the pump and the MAF they were still running bad, so I cut 1.25" holes in the exhaust ahead of the cats and the car ran great.
After cutting the cats off and checking them out the one on the right was at least 95% clogged. It looked like someone had poured pewter into the honeycomb. The one on the left wasn't too bad. Replacing the cats corrected the problem entirely.
After cutting the cats off and checking them out the one on the right was at least 95% clogged. It looked like someone had poured pewter into the honeycomb. The one on the left wasn't too bad. Replacing the cats corrected the problem entirely.
09-10-2014, 11:23 AM
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i have no cats so that couldnt be the problem in my situation but i guess i could have bought a bad pump to begin with? cleaned the maf with crc maf cleaner and it didnt help so maybe just a bad sensor idk.