bobo83

The issuse had started a few weeks back before Christmas. I originally the truck had no codes, just would limp to a start when it got really cold out. We are talking about < 0 degrees celsius. I then got a code of P2404 and replaced the vacuum pump as another member had that issue. Once I replaced it, I thought things where better, then, I started getting the bumbling start more frequently. I looked at my old HPFP and replaced it with the updated part number. Once, I replaced that, things seemed to be ok. Then a week later, I still get bumbling/balky starts every once in a while.

I hear the pumps prime when I open the door and I tried to pull the fuses to confirm, but a few questions for you.

When pulling fuses 13/14, should the truck die/stall out when pulled?
When I start the truck with either 13 or 14 in the fuse box, should the truck start?
When you connected the fuel pressure gauge to test the bar level, where did you connect it to?
Also, if my pumps are good, how do I test the fuel filter directly or do I just replace it?

scottl951

I'll take a shot here since no one else has.....

1-yes, but it'll use the rest of the fuel in the lines first.
2-I BELIEVE so, but not 100%
3-Should be a fitting somewhere on the fuel rail, don't know where.
4-Don't think you 'test' it. Just replace after like 100K or whatever service manual says. i did mine at like 110K and did notice a difference.

bobo83

Thanks Scott for responding back. I'll make sure the lines are clear when I pull the fuses to try to isolate the pumps. I popped off the vanity cover that says 4.8L however, I can't see the fitting on the fuel rail. The intake manifold seems to cover the rails, so if anyone has any idea of where it is that would be great.