Just noticed today that the oil pressure is way high while driving and not really moving even upon reaching operating temperature. Driving pressure at low throttle is 60-70 at full temp. and idling is right around 60. Here's the gauge, full operating temp. while idling...

Even before starting, the gauge shows 40, then after start up right to the 60-70 mark and doesn't move much. I'm hoping this is just the sending unit and not a bearing or electrical problem. Any insights? Thank you

ps...I know I have oil pressure because I didn't tighten the turbo oil return line enough and it was leaking, I tightened a couple days ago and no more leaks.

Just got some codes on the dash...

p0523

p0522

Both oil pressure codes, can I assume ALL I need is a new sending unit?

I would assume so. I dont think its anything more than a pressure switch, not really a pressure sending unit. As far as I know as long as there is more than 12 psi it just throws a number up on the gauge. As soon as it drops below that 12 psi, the gauge will go to 0 and it will probably throw a low oil psi light on the dash.

I think 2nd gens are actual pressure and 3rd gen is a dummy gauge

I would lean towards the sender also. If it is pricey you can run the diagnostics listed with the codes to be sure.

I think there are 2 or 3 different senders used on the second gens. The latest one is a switch and the older ones are pressure senders. I thought the switch came in around 2000-2001?

About 5 years ago mine took a dump.  They are pricey.  I looked in the Geno's catalog and it lists for $87 and it says for 98.5-02.  That is cheaper than I paid.

I've got 3 different part numbers going now. Cummins quickserve is giving me 3408429. Genos says 4326849, Hoelsi says and another site say 4921511. Might be stopping at cummins metro power this week

I was looking in the fall '13 Geno's catalog and is has the 4921511 that you have listed.  You can call them and pick there brains about if it will fit.  I found something on DTR about this.  Not sure if it helps you or adds to the problem.  Still worth a look.http://www.dieseltruckresource.com/dev/oil-pressure-sensor-4921511-not-right-part-t258872.html

 

If all else fails I would go to Cummins with the engine serial and get one.  That's what I did anyways.

I think 2nd gens are actual pressure and 3rd gen is a dummy gauge

The 2nd gens have dummy gauges. If you have the high idle mod from ed and turn it to 6cyl while the engine is hot the oil pressure climbs as the temperature gauge drops. At least that is the way it is on my 02 

I think there are 2 or 3 different senders used on the second gens. The latest one is a switch and the older ones are pressure senders. I thought the switch came in around 2000-2001?

 

...if this is true,

The 2nd gens have dummy gauges. If you have the high idle mod from ed and turn it to 6cyl while the engine is hot the oil pressure climbs as the temperature gauge drops. At least that is the way it is on my 02 

then this is true...

 

Then that means mine does not have a dummy gauge!

 

I do notice my oil pressure fluctuates in different circumstances. How can a dummy gauge do that? WHY would they have a dummy gauge with a sweep? Thats silly...

I know on the third gens the computer moves the gauge according to calculations. My thinking on why hey did this is too many people were watchjng their gauges and whining when something wasnt to their liking. Trust me i have dealt with these people. Ford does something wierd with their coolant, i cant remember right but there isnt an actual coolant temp sensor or something and the coolant temp us calculated. A guy i work with has a ford that was running crazy hot and the gauge ran normal. He asked and thats the explanation they gave him

I would test with a external mechanical gauge. You'll most likely find way different numbers than what's on the gauge now.

I stopped in to see my mechanic, our local diesel guy who works at a repair shop during the week and works at a performance shop specializing in powerstrokes on the weekends, he said oil pressure sensors going bad are a dime a dozen on 2nd gens, with my 5022/3 codes he confirmed our speculation.

I'll do the sensor change and oil/filter change since it's about time this weekend and report back with my findings and up to date part number for the sensor.

I found these on Rock Auto. Pretty wide spread on the prices and I dont know which one is right. The first one is $16.30 and the second is $132.79. 

http://www.rockauto.com/catalog/moreinfo.php?pk=933945&cc=1440064

http://www.rockauto.com/catalog/moreinfo.php?pk=945948&cc=1440064

I had a similar issue, my gauge will actually read full pressure with the engine off.

I installed a mechanical gauge and it was only like $40 rather than $90.

 

When the bell goes off and says to check the gages I look down at the mechanical gauge and shrug.

 

I highly recommend installing a mechanical gauge rated up to 100psi above the oil pump which is the easiest place.

Just install it with a copper line rather than the plastic ones they come with.

 

You can also get the sensor at a cummins shop for the same cost as Genos if you have one locally.

My stock pressure sender hasnt worked since I bought my truck. I have always just used a mechanical gauge after I heard that the stock one may or may not even read actual pressures. I do get the 0522 code but it doesnt set the CEL so it doesnt bother me.

Replaced the oil pressure sensor today and the in-dash gauge is back to normal. Idle pressure at full temp is back below 40, 0 pressure before start up, and the needle moves in correlation with the throttle. Still have the codes but I think I read somewhere they will go away once the truck gets driven a while. Did an oil change too but the sensor has to be the culprit, I'm pretty sure it was the factory sensor because the VOID sticker was still on the ECM harness and it had not been touched. New part was $90 from the local Cummins place, new part # 4326849. Oil pressure sensor is located under the fuel filter and ECM harness on the driver's side.

Quick Write Up

1. Disconnect 2 negative battery cables.

2. Remove two 10mm bolts holding fuel filter housing to manifold cover and push housing aside.

3. Remove one 4mm allen bolt from ECM harness and pull back harness.

4. If original unit, use a 32mm double deep socket to remove oil pressure sensor (old part# 3408428).

5. Use 1-1/16 double deep socket to install new oil pressure sensor (new Cummins part# 4326849).

6. Torque manifold/fuel housing bolts to 18 ft-lbs.

3 prong

New sensor is the smaller of the two...made in mexico

You can see the ECM harness pulled away and the oil pressure sensor/harness below it.

Just a quick note remember oil pressure sensors are not absolutely correct.

 

I would like to thank CTcummins24V for the quick write up and I've moved into the article database for others.

 

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/26-engine-systems/445-engine-oil-pressure-sensor

If you're young like me, the oil pressure sensor is very easily accessed from underneath the truck, without removing any other parts. Been there done that...