Hello new here I have a 2003 Tahoe 4.8l started with driving home from work one day driving and it stalled out would start back up but would not drive more then 2-3 hundred feet had towed home figured was fuel pump replaced it Friday. Monday morning go to head to work make half way stalls out again will start won’t move. Towed home again replaced pressure regulator and fuel lines and filter. Hook pressure gauge up only getting 45 pounds so figure maybe pump is bad get another pump same thing 45 pounds relay replaced for good measure no Change will run for 30 mins to 210 temp then seems to stall out at this point at a loss and just have no idea what to do gonna check injectors but don’t have a check engine light on any help would be more then appreciated !!
2003 Chevy Tahoe 4.8 fuel issue
- Thread starter Hyder12
- Start date
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Tonyrodz
Resident Resident
I had a similar issue in my 03 too. It used to happen driving up slight inclines or going up hills. Turned out the fuel filter had sediment and was clogging the lines when going up hill, cutting off the fuel making it stall. Never happened on flat roads. Changed the fuel filter and it went away. Has you changed your fuel filter yet?
I did but it seems to cut off on any type of ground and can’t get the fuel pressure up
43-45 psi fuel pressure is what these do when the engine is running.
When and how are you testing the fuel pressure?
Key on, engine off, with the pressure tester on the schrader valve on the fuel rail, what do you read? IIRC the 4.8 doesn't come as a Flex Fuel engine, so the spec for KOEO is 55-62 psi.
After the engine starts the fuel pressure regulator takes over and brings it down to the mid 40s, which is normal.
When and how are you testing the fuel pressure?
Key on, engine off, with the pressure tester on the schrader valve on the fuel rail, what do you read? IIRC the 4.8 doesn't come as a Flex Fuel engine, so the spec for KOEO is 55-62 psi.
After the engine starts the fuel pressure regulator takes over and brings it down to the mid 40s, which is normal.
Last edited:
nonickatall
Full Access Member
Did you try to open the fuel cap and drive? Propably you have problems with the evap system and due to vakuum in the tank you don't reach appropriate psi and the fuel pump can not suck enough fuel.
Also what psi should be at it’s a 4.8l non flex fuel
i have not put new pump in and tried to take for test drive and didn’t even make it out of the driveway and stalled out
Tonyrodz
Resident Resident
rockola1971
Full Access Member
Does engine immediately restart after it stalls? If so then tape fuel pressure gauge to pillar where you can see the pressure. Take for a test drive and see if the fuel pressure actually does drop. Doesnt appear that you know that or not so how do you know this aint a loss of ignition problem?
