Ok need help!

[killj0y]

Ok truck just suddenly died and won't stay on. Earlier today put in a new dpfe sensor to clear a p0401 code. Code cleared. Leading up to this my truck had been misfiring at highway speeds. Well after the new dpfe it still misfired.

Coil packs are new, changed the fuel filter earlier (that seemed to help it stay on longer) alternator is brand new just changed a week or two ago, wires are about a year old, has no problem cranking and will run strong for a minute or two after sitting a few minutes off.

I'm thinking fuel pump is going out, any other ideas?

Ps zero codes thrown!

 

[killj0y]

???

 

[snake]

That would be my guess as well, a fuel issue. Could be the relay (most likely), inertia switch, fuel pump, or fuel pressure regulator. You can rent or buy a fuel pressure gauge, hook it up to the rail, and watch it when it dies. If it is a fuel issue, figuring out which component went bad is not too bad- just determine if it is or isn't a fuel issue before throwing parts at it.

 

[killj0y]

Well I also did notice that last week my fuel gauge danced a little bit. And while it's true that troubleshooting helps narrow it down, the fact that it will still turn on and mostly stay idling (rough). Leads me to believe with everything else done that the pump is going out and therefore is weak. So it's building pressure but no where near enough. The line has quite a bit of pressure and fuel (noticed when I changed the fuel filter both times) maybe the fuel pressure regulator, but I suppose logic says the pump especially since as far as I can tell it's original...that's 200,000 miles plus on it. It makes sense it would crap out.

 

[killj0y]

Ok started her up this morning and she seems to be running fine what gives? Has her on for 20 minutes so far with no hiccups

 

[snake]

That could be electrical- that is, relay, or inertia switch. Heat usually makes those things go tits up. Some of the inertia switches get hot, wires melt some, connections get crappy, that sort of thing. I'd still get a gauge and check it to see where ur at.

 

[killj0y]

That could be electrical- that is, relay, or inertia switch. Heat usually makes those things go tits up. Some of the inertia switches get hot, wires melt some, connections get crappy, that sort of thing. I'd still get a gauge and check it to see where ur at.

Well I already have the pump so I'm gonna go ahead and change it out and cross my fingers. Got the bed up right now.

 

[killj0y]

Got the pump changed out and It runs good, but only time will tell. I have a filler neck on the way, wish it had been here so I could have swapped it out at the same time, but oh well. I'll update if it acts up again. Still no codes so far so good, and no more misfiring for now.

 

[snake]

cool beans