Engine/Transmission (1998.5 - 2002) completly stumped need help!!!!!!!!

[ShawnS]

Ok TDR members i need some help!! Hope its not too confusing but here it is...



My buddy is have some seriouse fueling issues. He has a 98. 5 24v he recently had the vp44 hot rod installed, he has Rv275 injectors, fass 150, edge comp box, hx35 hybrid... After about 6 months with trouble free problems one day last week he got a couple codes p0236 p0500 p1693 p0122. which the p0236 is the map sensor too high too long. so he went to cummins and got a new sensor and replaced it. Now the problem we are having, that there is no Smoke!!!!! Now before we replaced the map sensor the truck would smoke, but he has been having low boost issues (24psi on a hx35 hybrid) compared to 30psi when we installed the new turbo... Now with the comp box on or off and the new sensor in he is not getting even a slight haze, doesnt make any sense... For some crazy reason we unplugged the wire harness goin to the map sensor and the thing smokes like it used too but with no performace increase (still only getting 24psi)... Now why would the map sensor make such a big difference??? Performace is the same with the sensor plugged in or unplugged but when its plugged in it doesnt smoke which means its not getting the low end fuel that it needs, right??... Does anyone have any answers or suggestions??? Any help would be greatly appreciated... . Thanks Shawn

 

[Huff N Puff]

Sounds like the Edge Comp

Was not hiding the extra boost from the ECM,so it either has a wiring problem,probably a ground issue, or the Edge Comp has failed.

 

[ShawnS]

Its not the comp box because with this map sensor unplugged it has a haze stock, but when i turn on the comp it smokes alot. now with the old map sensor in, it smokes with the map sensor plugged in. i just get the p0236 code

 

[ShawnS]

Atleast im pretty sure its not the comp. Are you saying it a ground on the comp or anywhere on the truck itself???

 

[TDeltonto]

is the comp spliced into pump wire? Check the ground for the comp.

 

[TDeltonto]

also check the sublevel settings on the comp for low fuel boost just hold the power button for a couple seconds and release

 

[ShawnS]

we checked the comps sublevels for low fuel boost. he said its turned all the way up. im going to have him check the ground wire. but me and my buddy really dont think it has anything too do with the comp, because if we pull the plug on the map sensor its gets the fuel it is supposed too. The comp works with the new map sensor plugged in. It just doesnt get the fuel delivery. It gets the performance. just no fuel. Not even a haze. IF my buddy puts in the old map sensor it gets that extra fuel but a P0236. With the new map sensor no smoke.

 

[GCULP]

The comp works with the new map sensor plugged in. It just doesnt get the fuel delivery. It gets the performance. just no fuel

I'm confused here, if you're getting the performance with no fuel. I assume by reading through your posts you attibute smoke to mean more fuel, it might be that with the new map sensor you're getting just the right amount of fuel.

 

[Gary - K7GLD]

I had a similar issue, cleaned all the Comp contacts EXCEPT the plug directly into the Comp itself, because that plug is sorta hard to unplug in my setup - still had the same code issue, even after 2 sensor swaps - finally unplugged the Comp itself and sprayed with contact cleaner - and no more issues, even with the original sensor that started it all...

 

[Huff N Puff]

Atleast im pretty sure its not the comp. Are you saying it a ground on the comp or anywhere on the truck itself???

The Edge Comp needs to be grounded to work properly, the ground from the comp is a really small wire and with alot of engine vibration sometimes breaks it.

 

[ShawnS]

I had a similar issue, cleaned all the Comp contacts EXCEPT the plug directly into the Comp itself, because that plug is sorta hard to unplug in my setup - still had the same code issue, even after 2 sensor swaps - finally unplugged the Comp itself and sprayed with contact cleaner - and no more issues, even with the original sensor that started it all...

Gary are you talking about the plug to the comp inside the cab?And you said that you had similar issues. Could you please tell me what issues you were having.

 

[ShawnS]

Gary are you talking about the plug to the comp inside the cab?And you said that you had similar issues. Could you please tell me what issues you were having.

ok checked the comp plug and cleaned it, cleaned the map sensor and the IAt sensor. no luck still

 

[Gary - K7GLD]

Gary are you talking about the plug to the comp inside the cab?And you said that you had similar issues. Could you please tell me what issues you were having.

Yup - sounds like you got the right plug - my problem was the 1693 and 237/238 codes (as I recall). Those were indications of both too high, and too low manifold pressure/MAP voltage.



I bought and installed a known good, used MAP sensor, worked OK for a couple of weeks - and had ordered a new replacement "just in case". Got the code(s) again, installed the new replacement - and soon got codes again. There's a thread on TDR about my own instance:



https://www.turbodieselregister.com...8737-map-sensor-failures-24-valve-trucks.html



I had already thoroughly checked and cleaned all Comp connections EXCEPT the plug to the Comp, because to get at it, I have to drop my RV brake controller out of the way to get to the Comp.



BUT, since all else had failed - including switcing the Comp off and trying various different Comp settings, I finall went ahead and cleaned the Comp connections as well. They all - including the ones in the engine compartment, LOOKED all OK - but doing the ones direct to the Comp did the trick. After a while of driving around with the new replacement MAP with no further issues, I reinstalled the original once again, and all has been fine for over a year now...



These various connectors appear to all be of the "crimp-on" type, including the pins inside the plugs - and over the years, I've seen and experienced plenty of incidents where connections looked clean and proper externally - but hidden corrosion and failed contact INSIDE the connectors create problems and failures.