Truck died on my twice today as I was driving down the road. Nothing like trying to stop a 15,000 lbs loaded G/N with out any power.

Anyways, after I got it off the road I tried to restart it with no luck. After about 2-3 minutes the truck started fine. I drove it another 10 miles and it died again. Again, after about 2-3 minutes it started fine. I checked the codes and came up with a P-0088 and a P-0251.

I just changed out the FCA yesterday so now I'm clueless. Could my CP3 be going out?


Thanks,
Eric

 

Sounds to me more like a lift pump issue! Those CP3's rarely fail unless you are modded. I had to replace mine at 103,000 because of an internal seal leak, not because it quit. Have you looked into the lift pump? THose are pretty common on these trucks and my 2004.5 did the same exact thing you describe.

 

What gets me is the fact that it just completely shuts down without warning. And the other thing I dont understand is why it start up perfectly after 2-3 minutes. Then runs like nothing ever happened.

 

That really sounds like a lift pump.

What does your fuel pressure gauge say?

Your codes point toward your rail pressure sensor and the CP3, tho. They could be codes caused by low fuel pressure problems.

Pull your rail pressure sensor and electrical connector on your CP3, clean it with some alcohol and a soft brush, and apply some dielectric silicone.

How are your batteries? Pull the cables and read the battery by it self. If it's below 11v, pull them and get them load tested. Make sure the cables are not stiff and hard or corroded. Follow your ground cables, make sure they are ok.

Turn the key on and listen to the pump run in your tank. Take the fuel cap off and have someone turn the key on... it should be a solid hum for anywhere between 30 and 40 seconds... as long as it is a solid sound and then cuts off, it's ok. (to a point.)

If it stops running again, turn the key off, then back on and listen to the pump. If it is not running at all, bump the starter but don't start the truck, listen again. If you don't hear anything, that means the pump is bad. Usually you'll get a P0234 (I think that's it) code, low voltage from the fuel pump, but not always.

From there, I'd look at the rail pressure sensor, then the CP3. As stated above, I have not heard of a lot of bad CP3's.

HTH.

 

Fuel pressure guage? yeah, I need to get one of those

I have noticed that the only time this seems to happen is when I'm pulling a heavy load. Tomorrow I'm gonna pull a load to see if I cant get it to cut out again. If it does I'm gonna crack the drain valve in the fuel filter to see if there's any fuel in the bowl. I think you guys might be on to something with the LP going bad. Running the Juice on level 5 for the last 90,000 miles probably isn't helping it any. And with 160,000 on the stock LP

 

Go outside and listen to your pump...

 

I guess I'll go throw on some flip flops and venture out in the rain to go listen. Only for you hat... Only for you

 

Well, then don't do it. Drive it till it blows up, I don't care.

 

Okay Hat, so I turned the ignition onto start and couldn't hear the pump running. I decided to open the drain valve to empty the filter housing. I left the valve open and turned to ignition back to run to see what the fuel flow looked like. I had fuel coming out but not what I thought it would be. Seemed to be about a 1/4 inch stream of fuel? Not sure what the fuel flow should be.

 

You say you turned it to start... did you crank it or just bump the starter? Fuel flow out of the canister is not reliable. The only way you can check fuel flow from the canister is to drain it completely, close it up, then turn the key on until the pump turns off again, then see how much fuel you have.

I know it's raining, man, so don't go out there again tonight... just let us know what happens when you listen at the filler door of the tank. Have someone else turn the key on for you while you listen.

 

I just turned the ignition to run.. Didn't try to bump it. I can hear the pump run but I have to put my ear to the bed of the truck to just barely hear it. On past filter changes you could hear it 10 feet from the truck.. Then again there have been times I could barely hear it after a change

 

It could be the Juice causing the problem. Pull it off and see if it happens again.

 

This is true also...

 

Well finally found the problem. I found that 2 LP wires were chaffed causing them to arch. The only way I found it was from "jiggling" wires while the truck was running. After shaking the wires under the passenger side door the truck would shut off.. Still trying to figure out how in the world you get chaffed wires inside a wire loom?