Archived 12V low power after running a few miles

[Jff24Gordn]

This mourning I started my truck and it stunbled bad after it started. It wasnt plugged in at 20F. I reved it up at 1500 rpms for a minute and then drove to work. Its only a mile and never got to full throttle. A few mins later I drove 2 more miles at low speeds with some idleing inbetween. It sat for 20 mins and then I left to goto Louisivlle for stuff. When I got on the highway, I had very little power, maybe 100hp. I just made it to 55mph in 1/2 mile. It wouldnt top 10psi boost and when I floored it it dropped to 8 psi. It ran smooth the whole time. Never stumbled or missed a beat. I then poured a 60 gallon bottle of standayne preformance and let it idle for 10 mins. It didnt get better, but still idled fine. I let it sat for 3 hours and then drove to town for lunch, and it had about stock power for 2 miles then it started dropping power. It was off for 10 mins then drove the 3 miles back to work and it was dopping power the whole way. It sat till 5pm and it had some power, just not all of it, and it was dropping on the drive home.

I checked the turbo, and it spins freely. BHAF is dirty, but not bad. There is NO smoke at full throttle except if I rev on it then it has a littel black. I believe this is a fuel delivery problem on the low pressure side. Either one of the screens is plugged, the lift pump is going out, the filter is clogged, or the overflow valve is bad. my fuel gauge is out, and I have 180 miles on the tank. All unloaded.

Any ideas?

I am going to Cummins Cumberland in 1 hour for a few filters and an over flow valve and a bottle of algecide to cover my bases.

 

[pathaymond]

I would Change the fuel filter first. One bad load of fuel will muck you up. I know from experience my symptoms were same as yours. New filter and the beast came alive again Good luck.

Patrick

 

[BillGotthelf]

Pat change the filter first-its the cheapest fix-but it sounds to me like the same thing that happened to my 96 when the lift pump was going out.

 

[Jff24Gordn]

Talked to the shop foreman at Cummins Cumberland, and he thought it was the lift pump, but he suggested I do the cheep easy stuff first. So i have 2 filters and an overflow valve. Hopefully I wont be back for more parts. He also suggested to check the shutdown solenoid.



It makes sense that my lift pump would go out. I do once in a while make fun of 24V lift pumps.

 

[Jff24Gordn]

Ok, I just replacd the overflow and gave it a test drive. My boost is up from 15psi to 30psi. The valve was some of the problem. But I can hit 45 with ease. I'm letting it cool down for an hour and then will get the fuel filter. Expect a reply around 11:00. I am gonna cut the filter open to get a good look at it.

 

[Jff24Gordn]

A slow and painfull death would be too nice.

I didnt think it was the filter since I was pulling 6 tons on 2 lane highways at a high rate of speed for the first 200 miles on the tank. If it was a bad load of fuel it would have cropped up then.

I got the filter off and cut it open and what do i find???

Grease. about 6 ml of gease. Apaearently somebody thought my fuel didnt have enough lubricity, and added some to help. Must have been a single chunk in the tank and have gotten sucked up and deposited in the filter to take about 250hp off of the engine in 10 minutes of slow driving. I'm gonna go tomorrow and buy several more filters for other chunks that might be in the fuel and a locking fuel cap.

Who ever did this is awefull brave. All of my friends know I just got an AR15 and there were around 100 used shells laying in the bed from where I was using it as a gun rest.









btw this can be moved to the archive section.