'04 1500 5.3 Fuel Pump Sending Unit Nightmare

sy302 · December 7, 2007

I purchased a 2004 gmc sierra 1500 crew cab with the 5.3 engine about 4 months ago. It now has 46k miles on it and no warranty. The fuel pump went out. Local repair shop picked it up and diagnosed the fuel pump was bad. The closest dealership did not have a pump and the price was unbelievable for the pump and sending unit. I found a unit at Carquest and was told it was a Delphi pump, the same as OEM, and came with the new sending unit for $369. Part number was fg0340. I purchased it and had it installed. The pump worked fine but the fuel gauge didn't work. Took it back to the shop and they verified everything was installed correctly and told me I had a defective unit. I carried the unit back to Carquest and they gave me a new one. It was installed today and the fuel gauge is still not working. Any ideas on what the deal is? How can I determine if it's the sending unit or something else? At this point does it need to go to dealership? I'm really starting to wish I had spent the extra $$$ and purchased a new truck. Thanks.

atboley · December 7, 2007

you need to check for codes, see if it has any sending unit codes in it... could also be a cluster, sounds like to much of a cowincidence(or how ever u spell it). when you buy a complete fuel pump on some of those, it comes with a kit to re-wire the connector to fit a new style connector at the assembly. i bet they re-wired it wrong(mixed up 2 of the wires) , there is a bulletin out because the color wires on the new harness dont match... question them about it and show them this bulletin and MAKE SURE they wired it like it says...

Subject: New Fuel Pump Pigtail Connector Has Different Color Wires - keywords crank harness module nostart stall #PIT4067 - (07/06/2006)

Models: 2003-2005 Cadillac Escalade Models

2003-2005 Chevrolet Avalanche, Silverado Classic, Suburban, Tahoe

2003-2005 GMC Sierra Classic, Yukon, Yukon XL, Yukon Denali Models

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some questions have been received when installing a new fuel pump module and pigtail connector. The new fuel pump module has a new style connector and a new pigtail connector must be installed. In some cases, the new pigtail wire colors are different from the factory harness and no wiring diagrams are provided with the new pigtail connector. The wires in question are two Black wires on the vehicle harness and the Black and Org/Blk on the new pigtail.

Recommendation/Instructions:

Use the following to properly install the new pigtail connector:

Pigtail

Body Harness

Purple

to

Purple

Gray

to

Gray

Black

to

Black (the larger 16 gauge black wire)

Org/Black

to

Black (the smaller 20 gauge black wire)

atboley · December 7, 2007

ooops, that didnt post like i thought it would... suppose to be like this...

pigtail | body harnes

__________ _|________________

Purple TO Purple

Gray TO Gray

Black TO Black (the larger 16 gauge black wire)

Org/Black TO Black (the smaller 20 gauge black wire)

sy302 · December 8, 2007

The new pump did not come with a new harness. I checked on a harness when I was at Carquest and it wasn't required/offered. They want to take the pump out, get an OEM pump (their responsibility), and try it. I'm not sure about that but it won't cost me anything to try it. I thought about the cluster but it was working flawlessly before the original pump was removed. That would be an unbelievable coincidence.

C & A s Dad · December 8, 2007

I work for CARQUEST but do not have access to our cataloging at this moment. We do offer Delphi, Bosch and Airtex and our catloging does indicate the OE brand. Delphi is likely the OE brand for your truck and since we made this move approx a year ago, our Fuel Pump issues have gone away. The unit you received should be exactly like what was removed and not need any adaptors, harnesses etc unless the OE has specified such. I will not tell you we have never had a bad Delphi unit but the chances are very slim. The chances of getting two defective units in a row would be next to impossible.

Good, luck in finding the issue and if you need my help, I will be happy to do what I can.

Norseman · December 10, 2007

I work for CARQUEST but do not have access to our cataloging at this moment. We do offer Delphi, Bosch and Airtex and our catloging does indicate the OE brand. Delphi is likely the OE brand for your truck and since we made this move approx a year ago, our Fuel Pump issues have gone away. The unit you received should be exactly like what was removed and not need any adaptors, harnesses etc unless the OE has specified such. I will not tell you we have never had a bad Delphi unit but the chances are very slim. The chances of getting two defective units in a row would be next to impossible.

Good, luck in finding the issue and if you need my help, I will be happy to do what I can.

Yea, you've gotta have something else going on. Look at the connector (male), from what I understand, sometimes they are corroded and need to be replaced.

sy302 · December 11, 2007

Turns out it was the fuel pump from Carquest. Either it was not the correct pump for my application or it was a manufacturing defect on both of them. The float was not turned in the correct position and was hitting the side of the tank. The repair shop should have caught this but didn't until today. The employees at Carquest looked up the item number repeatedly and came to the conclusion that it was manufactured incorrectly. They stated it was the first Delphi unit to come back for any reason since they started selling those units 7 months ago. Maybe you could verify the application (C&A's Dad). Carquest refunded the pump and the repair shop picked one up from the local AC Delco distributor. Bottom line is that it ended up costing more than it would have if I'd just taken it to the dealer. I'm hoping that Carquest will come through with some help on the labor. Thanks guys.

Norseman · December 11, 2007

The repair shop should have caught this but didn't

It seems to me that the repair shop should be the one helping you with the labor. I've always had very good luck with my parts I get from Carquest are you sure you were giving them the correct info so they could give you the right part?

Anyway glad its fixed.

C & A s Dad · December 11, 2007

Turns out it was the fuel pump from Carquest. Either it was not the correct pump for my application or it was a manufacturing defect on both of them. The float was not turned in the correct position and was hitting the side of the tank. The repair shop should have caught this but didn't until today. The employees at Carquest looked up the item number repeatedly and came to the conclusion that it was manufactured incorrectly. They stated it was the first Delphi unit to come back for any reason since they started selling those units 7 months ago. Maybe you could verify the application (C&A's Dad). Carquest refunded the pump and the repair shop picked one up from the local AC Delco distributor. Bottom line is that it ended up costing more than it would have if I'd just taken it to the dealer. I'm hoping that Carquest will come through with some help on the labor. Thanks guys.

Sorry, I just got a chance to follow up on this post.

The FG0340 is correct for a 5.3 short bed. A FG 0383 is listed for a long bed and a FG 0392 is for the 5.3 Flex Fuel. The Delphi unit is the unit GM used from the factory. I have not seen the issue you described. You can certainly file a labor claim on the part or have your Installer do so. Be sure you let the store know you would like to do this so they will hold the pump until you can get the necesary documents together to file the claim. If they pump gets sent in as a normal defect, it will make filing a labor claim all but impossible.

If you find out for sure the Delphi units you received from us were assembled inproperly, would you please let me know by posting back here or sending me a Private Message through the forum. If they were assembled wrong, we want to be sure we do not have anymore on our shelves like this.

h e russell · February 13, 2008

Turns out it was the fuel pump from Carquest. Either it was not the correct pump for my application or it was a manufacturing defect on both of them. The float was not turned in the correct position and was hitting the side of the tank. The repair shop should have caught this but didn't until today. The employees at Carquest looked up the item number repeatedly and came to the conclusion that it was manufactured incorrectly. They stated it was the first Delphi unit to come back for any reason since they started selling those units 7 months ago. Maybe you could verify the application (C&A's Dad). Carquest refunded the pump and the repair shop picked one up from the local AC Delco distributor. Bottom line is that it ended up costing more than it would have if I'd just taken it to the dealer. I'm hoping that Carquest will come through with some help on the labor. Thanks guys.

Sorry, I just got a chance to follow up on this post.

The FG0340 is correct for a 5.3 short bed. A FG 0383 is listed for a long bed and a FG 0392 is for the 5.3 Flex Fuel. The Delphi unit is the unit GM used from the factory. I have not seen the issue you described. You can certainly file a labor claim on the part or have your Installer do so. Be sure you let the store know you would like to do this so they will hold the pump until you can get the necesary documents together to file the claim. If they pump gets sent in as a normal defect, it will make filing a labor claim all but impossible.

If you find out for sure the Delphi units you received from us were assembled inproperly, would you please let me know by posting back here or sending me a Private Message through the forum. If they were assembled wrong, we want to be sure we do not have anymore on our shelves like this.