Engine/Transmission (1998.5 - 2002) Ok, my truck is having sporadic fueling problems

[TomGolden]

I have searched for "defueling" and "hesitation" and found one close sounding thread by bboxall, but his symptoms don't sound exactly like mine.



Background:



2001 with the ETH motor - 100262 miles on truck/engine

Diesel Dynamics Stage 3 injectors installed at 12K miles

Edge Drag Comp installed at ~25K miles, VP44 wire is soldered solid

SPA digital fuel pressure (and other) gages installed at 45K miles

original lift pump failed and replaced at 50K miles



About a month ago, the MIL light came on. I cycled the ignition to get the codes. P 1693 & P 0237. So I unplugged the MAP sensor connector, cleaned the connector, added dielectric grease and re-seated it. Light went off after a couple days.



Another few days went by, MIL comes on again, same codes. But this time, I have an intermittent defueling going on.



When I say defueling, I mean the truck acts like there is no fueling box attached. I mash the go pedal to the floor, and the truck does accelerate, but just barely enough to notice. There is no hard launch that you normally get after the short delay for the turbo to spin up with all the extra fuel from the Comp box. So I don't have the full defueling, as in when the ECM goes into limp mode and you hardly have any fueling at all... I just don't get any extra fueling.



Now I have also completely changed out the MAP sensor, and cleaned / reseated all of the connections to the Comp box and used dielectric grease in all connectors. I have also run with the Comp completely shut off, although still connected, and there is no difference. I have run it on several different levels, and no noticeable difference.



Now for the part that makes me think it isn't a bad Comp box.



After I run the truck for a good 15 - 20 miles and the engine is fully warmed up, I hit the go pedal and the truck fuels properly - the Comp does it's thing and it's drag racin' time! But for the first few miles, nothing.



I have the alarm LED on my SPA fuel pressure gage set to blink at 10 PSI, and it never goes off. I keep a constant eye on the gage, and I never have less than 13 PSI, measured at the VP44. So I am not inclined to think my VP44 is going out on me.



My MIL light is still on, 3+ weeks solid now, and I still have only the 1693 & 0237 codes.



The truck is driveable, but I want my power back!



Any thoughts or suggestions would be greatly appreciated.



Thanks

 

[Hohn]

Tom, I'd still look at the Comp first. At least send it off to Edge and have them test it.



Odds are that you'll have a new one in the mail soon. --jh

 

[BarryG]

Mine acted like that for a while. Driving at speed and then go to accelerate and it would but very very slowly. I had done the clean and grease the connectors as well. I thought that fixed it but it came back about month and a half later. Mine did not act up as much as it sounds like yours is though. I had an ez and not a comp. I replaced the map sensor and my problem went away well seemingly anyway. However shortly thereafter my vp did bite the dust. My vp had good pressure to it as well. Was it really the vp dont know for sure, nor do I know that it was a bad map sensor. All I know for sure is that it hasnt done it since I replaced the map sensor and then a short time later the vp.

 

[Todd T]

Tom, when my VP44 went out it would do as Barry described; go to accelerate and it would barely go. it then started doing it on a cold start and drive off. after about three weeks of chasing my tail with no codes relating i finally got a 0216 and replaced the VP44.



mine has run fine now for over 22K but i've recently developed this surging when i have the TST on anything about level 2 and gets worse the higher the level i go to. the surging is around 1700 fades a bit and comes back around 1900.



I just PM'd BBoxall about his truck and he informed me he had no feuling box and the VP44 fxed him. this was after spending the money for new MAP, IAT, APPS and finally his VP44.



I dont know if this surging is now another symptom of a going out VP44 or not. I'm again chasing my tail trying to isolate it.

 

[TomGolden]

Thanks for the info guys. Since I have my Harley to ride to work, I can "afford" to send the Comp to Edge for diagnosis, and I will likely do that in a short time if I don't determine the problem before I get to that step.

 

[TGibbs]

another Vp bites the big one, mine is doing that exact same thing, I have an injector pump being made at II for me and a RASP coming from Olee at powerbypoole. I dont know what my fuel pressure is but those two codes you have are the same as mine.

 

[Fishin Guide]

Thanks for the info guys. Since I have my Harley to ride to work, I can "afford" to send the Comp to Edge for diagnosis, and I will likely do that in a short time if I don't determine the problem before I get to that step.

Edge's "diagnosis" process is to throw it in the trash and send you another.



FWIW, my truck is doing exactly the same thing. I added a Catcher and it's better, nut I have no real power until it gets up to 1800+ rpm and then it'll build boost from 25psi jumping to near 40psi. It's like someone switches a box on. This is not as pronounced with the stock ECM.



I have a TST, and I need to have at least level 3 to feel like there is any power. Lower levels of the box act just like with the box off, just everything happens faster.



i am going to put my truck on DDP's dyno tomorrow in order to see if the graph shows any signs of an injection pump on the way out. This is what we suspect. I have great fuel pressure (excess of 20 psi) and this has been happening with both an Drag Comp and the Catcher/ TST combo. Actually, it had more power on the borttom with the Comp.



I have absolutely no codes. No CEL. It sounds like your issue and mine are very similar.



Dave

 

[DMcPherson]

being a cummins employee and dealing with these things all day, i would have to say that it is a vp. I dont know the dodge codes, but if you have a local cummins see if they can connect it to insite and get the codes for you. my money is on 368. no communication to ecm from vp44

 

[DPS]

definately check your cheap options first but sure sounds like the pump is headed south. THese pumps can fail with proper fuel pressure, good fuel pressure is not a guarantee of long life, but it sure helps.



Josh



www.dieselperformancesolutions.com

 

[C.Solomon]

Mine did the same thing and it had me thinking it was the pump. After testing this and that it was the Comp box.

I had 2 mechanics tell me that a pump that is going out will throw codes right away.

ex. you clear them and they come right back.



So I send the box back to edge and they send me a new one and all is good so far.

 

[TomGolden]

Thanks guys. I do have a Cummins West shop about 30 minutes drive from where I work, I go there about once a year to buy fuel filters, coolant, etc. . I think I'll try the Comp first, and if that proves fruitless, I may take the truck in and have Cummins check it for me.

 

[DMcPherson]

when my vp went I had no check engine light. fortunately working at cummins has its perks, and when I connected it to insite, it had logged a 368 fault 255 times, (which is the max it will store) now its back to normal. I have seen a couple other truck not show a check engine light also

 

[TomGolden]

I haven't taken it into Cummins West yet, but late last week I did completely remove the Comp altogether. The next time I drove the truck, my check engine light went out, and has been out ever since. Truck still runs perfectly smooth, etc. , so now I'm going to re-connect the Comp and see if the CEL comes back on.



If so, I'm going to send the Comp to Edge and see what they can or will do for me.

 

[Boondocker]

I've been in a similar boat and these are my observations.

P0237 is low boost voltage signal - it will set the CEL.

CEL lit will make the truck defuel, ie. limp mode.

Get scanner and clear code, CEL out, truck runs fine.

P0216 - Injection Pump Timing Failure - does not set CEL.



I was getting the 237 code frequently enough to make buying a cheap scanner a worthwhile investment. This would happen with the Comp turned on or off. I disconnected the harness (MAP, Data Port, & Power) and never got any code while disconnected. I finally uninstalled it and haven't had any codes since. The truck has always run strong, but I do miss the extra power Now I'm on the waiting list for a Smarty. It's like waiting for an organ donor to die or something. Just to rub salt in that wound, I still have the boost elbow in, so I can't romp on it for fear of setting an overboost code (0234). Still have the code scanner just in case though



Neil