2jduenas
Newbie
Since I took ownership of my 1998 Chevy Silverado K3500 7.4L 454, the fuel gauge has never worked. I have replaced the fuel pump assembly, including the sending unit, three times. All the other parts I have put into this vehicle have been from the dealership, either AC Delco or GM original. I’ve also had the instrument cluster tested, and it checked out fine. I’ve probed the wiring extensively to ensure there are no shorts, and I even replaced the ECU, thinking it might be a computer issue since the fuel signal runs to the ECM before reaching the cluster. Additionally, I changed the fuel pump relay and checked all my fuses. Despite all this, the problem persists.
Additionally, the truck runs poorly at idle. Interestingly, if I cut the purple sending unit wire at the fuel pump, the truck runs perfectly, though it throws multiple codes, including:
- Ignition on: P0452 and P0463
- Engine running: P0107, P0405, P0463, and P1107
If I leave the purple wire from the fuel pump connected, it will only throw two codes:
- Ignition on: P0463
- Engine running: P0463 and P0102
When I fill the tank up completely, the truck will stall out, but once the fuel is around half empty, the truck runs fine.
I am at a loss and need help. If anyone has experienced this issue and found a solution, I would greatly appreciate your advice. I’ve been dealing with this for a few years now.
Additionally, the truck runs poorly at idle. Interestingly, if I cut the purple sending unit wire at the fuel pump, the truck runs perfectly, though it throws multiple codes, including:
- Ignition on: P0452 and P0463
- Engine running: P0107, P0405, P0463, and P1107
If I leave the purple wire from the fuel pump connected, it will only throw two codes:
- Ignition on: P0463
- Engine running: P0463 and P0102
When I fill the tank up completely, the truck will stall out, but once the fuel is around half empty, the truck runs fine.
I am at a loss and need help. If anyone has experienced this issue and found a solution, I would greatly appreciate your advice. I’ve been dealing with this for a few years now.