Engine/Transmission (1998.5 - 2002) Engine, miss, stumble, lagging!!!

[KWheaton]

Been having this problem intermittently for months. Searched thread after thread with no one describing my problem exactly. Unhooked EDGE COMP, less noticeable, but still there. Worse when cold and/or towing.



THE LAGGING:

Cruising at highway speeds, accelerator pedal will just sort of "go limp", for lack of a better term, then she'll take off real strong again. Sometimes, it won't accelerate as normal, takes a little more pedal.



THE STUMBLE:

Accelerating, hard or soft, it bogs down, accelerates hard then bogs down again. Cruising along at 45-70, the tach will jump around 150-200 rpm, feeling a lurching or chug and a BIG hesitation or lag.



THE MISS:

Hard acceleration feels like a gasser with a bad spark plug wire, intermittent miss fire or the timing advance is off or really big vacuum leak. But intermittent.



Codes are:



0622: Generator field not switching properly. (Noticed a little high voltage on the gauge, nowhere near the top of the normal range though).



0753: Trans (DTT)

1765: Trans (DTT)

1693: ECM PCU DTC Detected? Can someone explain this?



0236: Map sensor (Over Boost?)

0238: Map sensor (Voltage?)

1475: ECM Aux 5 voltage too high?



Some of these codes may be from the edge ground wire being off when the engine was running (check engine light came on then). I checked my codes right after that.





ATTEMPTED FIXES:

Always use Stanydyne diesel fuel treatment. Changed filter last week, very clean after 10,000 miles. Vp44 was changed 10,000 miles ago (was bad). I thought I was periodically getting some water in my fuel, so I bought a few tankfuls at different stations. Fuel treatment should help with that too. Flip the drain on the filter cup periodically, put a glass cup under it once, fuel was water free.



Moved the EDGE ground to the battery with soldered connections, cleaned battery terminals, (Weren't bad anyways)



Checked pump wire, looked good, greased and put back on. . Blue chip pump cover is clean and dry, checked needle screw, looks good.



The more fueling I apply with the edge, the more noticeable the problem is, of course.



I considered the APPS, but I never get a dead pedal, and it's not showing those codes.



Fuel pressure is good, 13. 5 at idle, drops to 7 at wide open.



HELP!

 

[KWheaton]

Oh yeah. The other EDGE connections look pristene (like brand new).

 

[Lsfarm]

Boost messages

Kevin, see if the boost voltage and overboost codes stay there after 6 cycles. [start up, drive, shut down] If that boost code is still there, it may be the Map sensor, or the boost fooler circuit in the comp.



Call next weekend, and maybe you can come by and borrow my comp, and you can see if the problem follows the box or not.



LsFarm.

 

[KWheaton]

Cool! Sounds good. Talk to ya on the weekend.

 

[CSnyder]

Kevin, Before you try the box swap I would try swapping the APPS first because your symptoms are identical to the ones Ive had with the last 2 failed APPS sensors. Hope this helps, Chris

 

[KWheaton]

HMMMM... ... . Don't have a spare laying around. Electrical components are none returnable. Gotta say I'm going with the user serviceable (free) items first.



Engine ran good/better after warming up for an hour yesterday, although I detected a miss when I jumped on it in front of a friends house. I'll check codes again today.

 

[CSnyder]

I was suggesting trying LsFarm's APPS instead of the box. I would think the APPS would be a quicker swap than the box to check for trouble. I have a spare APPS that only has one dead spot right at 55 Mph in 5th gear I could send for you to try if LsFarm doesnt want to remove his. Sometimes these sensors will get erratic all over the pedal travel and sometimes its just in one spot.

 

[KWheaton]

Got ya. Swapping the box is just a plug on the back of the unit, under the dash. Wiring is good, just gonna swap boxes for a few minutes and give it a whirl.



LsFarm is the closest thing we have to a Dodge/Cummins mechanic (who doesn't work at a dealer) around here. If he doesn't track it down, nobody will. Thanks for the info. I'm sure we'll be looking at everything.



Codes have gone unchanged this week. Might be the map.



I just put $300 into my snow plows and $125 into a front axle u-joint, not having a good week.

 

[KWheaton]

Well, we tried the Edge swap... ... . same problem. Cleaned and greased all electrical connections last night, thought that was it. Today, same problem on the way to LsFarms house. After swapping boxes and heading back home, no more trouble. Really scratching my head now.



Will a MAP sensor act up intermittenly? Going to check the Map sensor supply voltage and ground. I'll post when I find out the REAL problem.

 

[Texas Diesel]

Same here. I was sure it was caused by my LP's.



After a year of no problem, it happened twice last week.



been through 3 LPs and 1 VP-44. Getting super boost code and another code for boost lower than expected (?)



So, its not the LP or VP... WTF? Has been ok since. Suspect MAP sensor.

 

[KWheaton]

VP is pretty new on mine. LP pressure never waivers, so I'm not suspect of fuel delivery, although something is telling the VP to NOT send fuel, therefore, the stumble & miss.



Haynes Repair Manual says to check the MAP sensor supply voltage (orange wire), it should be around 5v, then check the ground with an Ohm meter (black/blue wire), if these two are good and a boost trouble code is still present, replace the MAP sensor. I'll do this tonight, just don't wanna spend $91.



Good luck with yours Texas!