Replaced fuel filters a couple weeks ago around the time i finally cleaned the turbo. Truck has been running great.

The other day, i go to start it in the morning and fuel pressure didn't want to come up. After a few cycles it got to about 55psi, and drove fine. Did it again another day. Pressure eventually built to 75 whole driving. And once everything was warmed up it worked fine throughout the day when i went to start the trick. This morning pressure would not build past 15-20psi. After a few cycles i said forget it I'll take the car instead.

I'm guessing the fuel pump is bad, I've seen other stuff about fuel pickup problems. Any ideas on troubleshooting?

Also i was shopping for an HFCM, but i saw just the fuel pump by itself. Anyone familiar with replacing just the pump on the HFCM?

 

If the problem started after a fuel filter change, then the first thing to do is pull both filters and make sure they are installed correctly. Sometimes a bad install on the pump filter will do what you describe.

Replacing the pump in the HFCM is very easy, but do to its location many would be better off doing the repair on a bench so the lines are not in the way.

 

Sounds good, I'll check the filters before just replacing the pump.

To remove the HFCM I'm guessing I'll need a fuel disconnect tool. Sure i can figure it out but any tips or tricks?

Thanks

 

It getting close to a decade when I relocated mine. I would first take carb cleaner and with wearing goggles clean the connections, pulling the engine side retainers off first. The engine side connectors are what use the typical sleeve type tool used on fuel, trans and A/C lines. The tank side connectors I believe I just pushed in the release on the connector itself. Both cases, first move towards the hfcm before pulling off. The electrical connectors all have the typical release tab. Three bolts hold the hfcm to the rail.

 

Ok, thank you. I appreciate the info.

 

If it is the pump, this may come in handy.
Good Luck
Ed

 

Rusty replaced mine while on my truck. Took him 15min.

 

Perfect video for this.

 

Well that answers a lot of questions. Still need to get parts ordered. Drove the truck to work this weekend later in the day, outside temp around 70. Struggled to build pressure at first, but after a few cycles it was ok.

Thanks all, I'll give an update once it's fixed - hopefully this weekend

 

Low fuel pressure will kill injectors, I wouldn't drive it

 

Yes i agree, I'm not driving it with low fuel pressure though. Pressure comes up fine once it's started, but it takes a few cycles of turning the key on and off to get it to 55psi before i would start the truck. After that I'm getting 70-75 psi once its warmed up which is odd because its usually between 60-65psi.

 

I looks like you might be able to even replace the pump without removing the fuel lines if you really wanted.

I'm not sure but if you're getting more pressure than normal I would guess its the return spring (blue spring) as that is what controls the pressure (depending on where it's measured)

 

You also should check for air leaks. Two or three cycles of the key and pressures back... sounds like a leak to me.

 

Well i replaced the fuel regulator and checked, still not working correctly. Replaced fuel pump and still not getting pressure. Not really sure where to go from here other than dropping the tank.

 

Had to recharge the batteries overnight from cycling the ignition on and off they were very low. Checked it this morning about 50 degrees out and only got about 5psi on my fuel gauge. This afternoon after 8 cycles fuel pressure was above 50 so i started it. It came up to 65 after a few minutes idling so i took it for a drive. It's driving great and fuel pressure does not drop while driving.

I'm thinking as mentioned above it is a suction problem. Not really sure where to go from here, but I'm planning to drop the tank and check the fittings/pickup and do the harpoon mod.

Any suggestions or advice here is appreciated, maybe an aftermarket pickup and fuel line to the hfcm? I'm going to do some more digging this week and see what i can find out.