PJveetwin

Looks like I have a serious problem..... While towing a car trailer, I noticed a lost of power, then oil pressure started dropping quickly, eventually to nothing. Pressure was around 80 before. I was able to get off the road with a minimal time of no pressure. Motor still sounded fine at idle, water temp was normal. Engine has 150K on it, always changed with Rotella and was full. Can anyone offer some in sight? I'm 250 miles from home, AAA will be taking us home but still need to figure out if it needs to be rebuilt or what failed? Hard to believe the pump failed? Thanks in advance!!

patdaly

If it still runs, I would put a mechanical gauge on to verify lack of oil pressure.

Not sure if there is any correlation between loss of power and low indicated oil pressure unless a loss of power to ECM somehow, not totally, just low?

Hopefully a 24 valve guy will jump in here.

PJveetwin

Good advice! Hopefully this evening I can read the code and have a direction to work towards. Will post my findings. Thanks

PJveetwin

OK, have 2 codes for now

PO237 Turbo/Supercharger Boost sensor A Circuit low
PO341 Camshaft position sensor A circuit range performance (Bank 1 or single sensor)

OK, I’m a little green here, can anyone share what these mean?

Now moving to instal a mechanical oil pressure gauge.

DIESELWRKS

see if this helps at all.

http://articles.mopar1973man.com/2nd...signal-missing

PJveetwin

Thank you Dieselwrks,

I appreciate the help! After my last post, I ran the codes again, still the same, then I did something stupid like wiggle the connection at the oil pressure switch, erased the codes and ran the motor again and pressure came back and no codes...... I live in a dry climate so corrosion is not an issue, wires and connectors look good, so Did I find the problem?? Not sure?? Should I replace the oil pressure switch just because....maybe I should. Tomorrow all the connections are coming apart and cleaned with contact cleaner, one at a time and tested. Then kept locally until I feel comfortable with the repair. Nothing worst than working on an intermittent problem.

At least it’s something other than a lost pump and motor . Now does the computer have a safety feature that shuts the motor down if oil pressure is lost?

Thanks again

Mike L

When my oil pressure guage dropped to zero psi i experienced no loss of performance or power. I think that you perhaps have two issues to deal with. 1st, of course, is the pressure guage. Secondly you need to pursue those other two trouble codes relating to CPS and Boost. These DTC's didn't fire off for no reason.

Cheers!

Mike

PJveetwin

Thanks mike, Now that it appears to be intermittent, it should be fun. Thanks for clarifying they are not related.

Jim

patdaly

You don't happen to have a bunch of oil around that connector, do you?

It might be possible for the oil to become a conductor and bring the voltages down to where a DTC could be thrown.

Us 12 valve guys have a similar issue with our ESS sensors, we clean the connector with contact cleaner and she is good.

That is total speculation, but as good as anything else I can think of.

PJveetwin

Thanks Patdaly, I have a 4 post Bend Pak lift and I’m pretty good at pressure washing everything, but I’m now cleaning every connector in the hopes it solves the problem as now all the codes are gone and oil pressure gauge is working. Time will now tell

DIESELWRKS

I really like the moparman74 website as it tells you nice step by step trouble shooting for all the sensors and codes. telling you exact voltage , ohm etc. do some looking on his site under all the areas you would be amazed to see all that free help.
I second the other codes that tripped. if you have not all of your battery cables pos/ neg. and all engine and body grounds i would clean,scrub and protect. our finicky trucks are super touchy with sensors, etc etc. gremlins gremlins gremlins. take the time and do some of the step by step trouble shooting and this may Sir save you time and money with the root issue.

drewk88

The oil pressure and MAP (boost) sensors both get their 5 Volt supply from the same ECU pin (10). So that could be the link between losing the oil gauge and loss of power at the same time.
The camshaft position sensor gets its 5 Volt supply from the ECU pin 3, but maybe it's being affected by an intermittent short to ground in the orange (pin 10) circuit which supplies 5 Volts to the other two sensors. (Oil pressure & Boost)

https://www.dieseltruckresource.com/...d.php?t=311336

PJveetwin

A big thank you Drewk88 and Deiselwrk’s! That all make good sense, and I will double check it today

SIXSLUG

Grounds and battery cables??