Purpose of Oil Pressure Guage???

[Happy Camper]

I posted awhile back the oil pressure went to zero and never came back. The dealer flashed it and it varied between the first mark and the 3rd mark. (second mark is 40)for 10 miles and then settled down to 40 no matter what. A few days later it decides to go up a little past the 3rd mark. The mech said "this is normal"



Now I am noticing when I shut it off it naturally goes to zero. 30 minutes later I turn the key on (engine not running) and the oil pressure is reading on the 3rd mark. How can you have oil pressure when the pump is not running. Why not have a guage indicater with the needle pasted on? Why fuss with the wires and the plug in the block called a sending unit? Maybe it has done this all along and I was to dense to see it. Any Advice???

 

[Evan A. Beck]

Mine did the same thing, went to the third mark--even with the engine off. I replaced the sending unit, and it worked great. No reflash or anything...

 

[Happy Camper]

Thanks Evan. I will call the Dealer tomorrow and see if they will replace it under warrenty. If not Cummins gets the call. I can see where DC can almost dictate to the mechanic what they can and can not do under warrenty. Anyway I will find out soon. Thanks.

 

[Ram4Sam]

HC, that is exactly what mine did a few months ago. They did the reflash only and the gauge did just what you saw. Took it back and they replaced the sender and it has been okay since.



Sam

 

[MCummings]

The ECM/PCM tells the Oil pressure gauge to read 40Lbs if the Oil Pressure Sending Unit sends a signal that is out of the "Correct" range.

What this does for Dodge is a simple reflash of the ECM/PCM software, instead of having to replace the Oil Pressure Sending Unit. Much Less $$



MerrickNJr