I had a strange problem with my c5 today. Spent about an hour driving up the highway and parked the car for about 15 minutes. Started it back up, put it into reverse let out the clutch and it stalled. Started it back up, it ran for 2 seconds and died. I held the accelerator to the floor, cranked it over and it started, as soon as I let off it died again. Held the accelerator down, started it, let off and as it began to die I held it all the way down again, it hesitated for a few seconds and revved back up, did this a few times until it would idle and though I was home free until I let the clutch out and it died.

I had just under a half tank and figured maybe it was the dreaded jet pump failure and it was out of gas, so I limped it to the gas station in first gear at full throttle sputtering and surging the whole way, filled the tank, it started up and purred like a kitten and ran fine the whole 30 minute drive home.

Now, there were no codes and the fuel gauge read normal the whole time, and filing the tank definitely seems to have "solved" the problem. Does anyone have an idea what could have happened?

 

I expected a cel if there were codes. The only reason I wondered if it wasn't actually out of fuel was that I drove 1/2 mile or so to the gas station at wide open throttle and it never stalled

 

28-tcs
C1255h

40-bcm
B0432h
B0503h
B0508h
B2592h

58-sdm
B1001h
V1096h
V1064h

99-hvac
V1160h

Ao-ldcm
B2282h
B2284h
B2262h
B2264h
V1064h

A1-rdcm
B2283h
B2285h
B2265h
V1255h
V1064h
V1016h
V1096h

A6-scm
B0851h

Bo-rfa
V1255h
V1096h
V1064h
V1016h

 

Yes, my mistake, they are "U"s

 

I went through all the codes, most of them are loss of communication codes probably from a dead battery, noting fuel related

 

This kind of sounds dumb, but since we have "2" tanks take the passenger tank and hit it with a hammer so you can hear how it sounds, then hit the driver side and listen. If the secondary pump is failing to send fuel to the other tank you will be able to tell by the sound if one has gas and the other doesn't., Another way to tell is go to a parking lot and drive to your left and see if it sputters or hesitates. Obviously do this while you are at the same you were at when it acted up.

 

you need to disassemble a lot to get to the tanks, my plan for testing the pump is to fill the car, unhook the line from the fuel rail and pump gas out into jugs and see if I get 9 or 18 gallons out.

I more or less wanted to find out if the symptoms sound like a jet pump failure before going through the effort of diagnosing it

 

Just a thought - could be the fuel filter.