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fish biting?

buddy, thank you, resistor seemed to fix stumble. my question is, will that cause my p0251, and p0370 codes? or am i looking at two different problems? we will be taking a 2400 mile round trip this summer, and i don't want to have any trouble on the road with wife, and kids. not with the wife and kids i mean with the pickup...LOL
 
Well give it a week before we call it good :)

Those codes are more likely caused by clouded fuel, and some additive is settling the fuel maybe. Make sure you put some lubrication in it with the Stanadyne which doesnt rate very high on lubricity. Or some Seafoam diesel conditioner.
 
same tank of fuel, as when i took the top off of IP, fuel was clean, and clear. i will replace the temp sensor, it may still be original. does the sensor have its own code? the truck would stumble and fart all day long sometimes, and never set a code. then other times, one small hiccup, and i got the two codes.
 
I've been running 1qt SAE 30 non detergent to my fuel with my PS Grey additive, my truck seems to like that. Optic IMO only becomes sensitive to fuel opacity when running "black stuff" WO-WVO blended with fuel, I ran straight red for a while post Katrina when it was legal to do so, no issues whatsoever, I also would "dispose of HAZMAT" red when we had to change filters pre engine test at the jet test cell I used to work at, that required fresh filters for test, when we drained the towers that fuel was considered to be hazmat, and rather than pay a hazmat guy to come get it I'd "take care of disposal" and save the company money :D.

Could do the same now, but that would get some odd looks at the Diesel locomotive shop I work at now, that I might be getting more than just waste Diesel fuel.

It's hard to diagnose IP codes, as been my experience IP can set sympathetic codes, which are result of fuel issues out of the IP, turning it to a chicken or egg, which came first debate.
 
He should replace the CTS first.... Especially since it is a fairly cheap part. The PCM needs a variable reading to work properly.
 
indybeck said:
i will replace the temp sensor, it may still be original. does the sensor have its own code? the truck would stumble and fart all day long sometimes, and never set a code. then other times, one small hiccup, and i got the two codes.
Click to expand...
No code for CTS, you need a scan tool though to see what PCM thinks it's seeing, look for a post by ChrisK1500 for resistance vs temp, which will let you know if CTS is putting out correct resistance value for the PCM to react to.
 
i will replace sensor. as far as IP goes i think i will wait just a bit, like buddy said. i'll take a couple of trips, and see how it goes. really i only set codes when i stop at two or thee different spots, and let it sit awhile at each. last time happened at a stop light in town. i have heard of OS getting cooked, but i don't know symptoms.
 
used ohm meter to do a realtime check, and WTS is ok, but a new symptom just reared its head. truck didn't want to start. IP problem?
 
no hiccups or farts, check engine light just came on. was at an idle. i have stanadyne, and PS gray in tank. and yes, no. 2 ULSD.
 
Indy, when it was running did you ever try the IP test I suggested in post #28? Its a good indicator of IP health.

Early on you mentioned you had 5.5 psi fuel pressure at idle. Did you ever test fuel pressure while driving? Your idle pressure tells us you have a working lift pump, but to know if its feeding enough volume of fuel under load you have to have a guage you can read while driving. You said it didn't want to start, does that mean you couldn't start it at all, or did you get it going with a lot of cranking.

It would help to verify that your lift pump is OK, and that your IP can deliver fuel smoothly up and down the rpm range. It seems like the focus has been on electronics without ruling out basic fuel delivery.

Disclaimer - I'm a rank amateur at this, not as experienced as the other posters who are helping you!
 
yes i did it about an hour ago. and it doesn't come back down to idle smoothly. i have 3.5 psi cruising down the road. i got it started not with alot of cranking, but much more than usual. and don't feel bad, i am a "mechanic" at work all day long, and i am here trying to find out how to fix my 6.5. mechanic can be used as a very loose term. and i am not afraid to tell anyone, that i am not the best, or that i need help. thanks again guys for all of the input!
 
3.5 at cruise is enough to rule out the lift pump, though if you drop much below that when you are hard on the throttle you may want to look at a new LP.

I'm trying to remember without re-reading the whole thread - have you been able to try a known good PMD to eliminate that as a possibility?
 
replaced PMD, and lift pump. OPS has been replaced, removed sock in tank, and installed inline filter, new rubber hoses, cleaned OS. checked for air bubbles on return line. i may have forgot something...LOL
 
Well it would probably start better with the PCM not thinking the truck is 180*F, becuase it will cut your GP cycle short and not advance the timing. So thats why you need a working CTS, and not just a jumpered resistor :)

So try starting without the CTS plugged in and no resistor, then put the resistor in and see how engine reacts.
 
i agree, was tougher to start this morning. but truck was warm. sat for maybe 10 minutes. well, any other suggestions? otherwise i will be calling pensicola tomorrow. i am out of ideas. i did replace the WTS, but turns out it's not the problem.
 
Before replacing IP or something I would make sure the lines from top of the fuel tank to the IP are all good and you cant see all of them necessarily. The line from the filter assembly to the IP could be damaged. Usually everyone has rusty lines coming out of the fuel tank.

Air in the fuel can cause the issues.
 
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