Couple codes with check engine light

[Cummins12V98]

Started the truck the other morning it usually instantly fires. It stumbled a couple times but started and sounded fine. Took off pulling my boat taking it easy and all of a sudden it took off like i hit the accelerator.

Continued and it ran like it had no boost and the longer I applied the throttle it would "wake up" and run normal. Then once I let off it would start over again.

Codes are PCU 1693 and ECU 0237 Check engine light is on.

Looked this up and one YouTube mentioned his map sensor was the cause and he showed a deteriorated "O" ring. Thoughts???

MAP SENSOR - CUMMINS ('01-'02, 5.9L)
Item #: 4921505

 

[Cummins12V98]

I removed it's connector and looked nice and clean, I also looked inside the two larger connects at top of fire wall and they looked like new. I have done the Altenator/VP pump ground wire mod and it is done properly and battery cables.

 

[Ozymandias]

From the codes itself it doesn't look good.
Mopar1973Man says to the first one loss of communication between ECM and VP44 and for the second one boost level to low.
Do you have a boost leak by any chance?
Still doesn't explain the first Code- was it an active Code or stored?

 

[Cummins12V98]

Ozy thanks for the response. I am not a tech guy so I have no idea what active or stored means.

I was planning to remove the sensor tomorrow to see if the O ring has failed. I will check all hoses but I doubt I have a leak.

Drove it today and it runs and shifts perfect. If I add go pedal it takes a few seconds but it takes off like normal. If I want it to take off quicker I drop a gear and it wakes up sooner.
I hear no unusual noises like a boost leak. I have zero black smoke at all.

instantly started today no stumble.

 

[NIsaacs]

Do you have a programmer on it?

 

[BarryG]

Its been a while since I had my 01 but iirc the 1693 is a companion code which means there is at least one code in the other computer (pcm) dont remember it meaning anything other than that. i know on my 01 that code would show up occasionally but always when there was another code in the pcm. It was never by itself As far as the 237 again iirc low voltage to/from the map sensor. i had that code show up a few times first time it was also along with a vp 44 216 code which in the end was covered under warranty (the vp44 that is) the second time it showed it was a bad map sensor, the third time it showed along with some other codes was due to bad cps sensor.

When it showed with the 216 there were definite drivability issues due to vp44 crapping out. When the CPS went out and also showed that code there were a variety of other codes and there were definitely drivability issues actually it drove mostly ok except the tach and rpms were very erratic it might drive fine but show like 500rpms or show 0 rpms while driving fine or the rpms would be fine but they would fluctuate noticeably on the tach and in the engine as well and sometimes the tach would be erratic but the engine ran smooth.

So with no other codes aside from the 1693 I would target the map sensor. I think if you look hard enough on this site you will be able to find the resistance values on that sensor and be able to test it. or in the absence of that here is a link to moparmans testing procedure
https://mopar1973man.com/cummins/ar...odes_94/p0237-map-sensor-voltage-too-low-r65/
I doubt you have a drbIII scan tool laying around to perform all the tests but part way down it switches to using a volt meter for some tests. Might be helpful.

 

[Cummins12V98]

Do you have a programmer on it?

No, only mod is the AirDog and 275 Bosch RV Injectors.

VP is original but the original owner added the AirDog early on thankfully!!!

 

[Cummins12V98]

I have read the 1693 is an associated code several times. I did read about testing the sensor somewhere, now I need to find it. Geno's seems to have the best price at around $198 but that is an expensive give it a try.

 

[Ozymandias]

Do a proper diagnostic first before using the parts gun.
The self diagnostic ability of these Gen2 trucks is very limited and therefor you need to look at it as a ballpark. No more then a guess.

No smoke doesn't mean no boost leak, the MAP controls the fuel ramp, if boost stays down or doesn't rise according to the expected value it won't ramp up the fueling anymore. So No smoke.

Mechanical problems are "invisible" to the ECM, so it takes the next best thing and shows this as a fault, like a faulty MAP sensor to you bit actually you have a boost leak.

Your 15 has way better built in diagnostics but still can't see mechanical problems.

 

[Ozymandias]

Just as an idea, on my buddies 98 the hose between Turbo and Intercooler shrank somewhat so the hoseclamp was slightly loose, tearing the hose with the clamp from the IC inlet pipe. It reacted very similar as yours.

 

[Ozymandias]

An active code means the fault is present at the time the diagnostic is done.
A stored one can be years old and only happened once.

It is essential to keep these two apart in the process diagnosing the truck.

Codes do not necessarily mean a lightened CEL, just a small amount of codes actually light the CEL.

 

[Cummins12V98]

Heading to shop now will update.

 

[Cummins12V98]

Sensor "O" ring looked good. Tightened all boost clamps and hoses looked good.

Carquest owner I know ordered me a sensor and said he would lifetime warranty it. I know, I know.....Cummins is the best but I don't want to wait. In fact if this is not the problem he will take it back.

Will update tomorrow.

I am leaving ground cables disconnected overnight and will not connect until the sensor is installed and ready to start.

Let me know if I am missing anything.

 

[BigPapa]

What truck is this? Your signature says 2015.

 

[Cummins12V98]

What truck is this? Your signature says 2015.

Sorry it’s a 01 automatic

 

[Cummins12V98]

Replaced sensor, connected battery negative cables. Started engine and check engine light is still on. Took it for a spin, all is normal in the performance department. YEA!!!

Now how do I get rid of the check engine light and the two codes that are still there???

 

[Topzide]

They'll go away after key cycles or clear with a code reader. Glad to hear you got it up and going!

 

[Cummins12V98]

They'll go away after key cycles or clear with a code reader. Glad to hear you got it up and going!

Thanks!

Don’t have a code reader, I just did the key cycle. So will the CEL and codes go away on their own?

I am happy the new sensor fixed the issue!!!

I appreciate everyone’s help.

 

[Ozymandias]

The CEL will go away, the codes maybe. I'd see a dealer to erase them, otherwise at the next fault you have the same problem as now - don't know if active or stored, reading them through the tach.

 

[BarryG]

IIRC on my 01 depending on the type of code some would go away immediately and some required a few (thinking it was 2 or 3) drive cycles which again iirc were not just starts but heat up and cool down cycles.