Engine/Transmission (1998.5 - 2002) Knowledge...

[CM_Guest]

Someone "knowledgeable" told me that a new factory reflash for my PCM would turn my oil pressure gauge into an "idiot light". The funny thing is that the reflash seems to have done just the opposite. There is a lot more gauge movement between high and low idle speed oil pressure now than there was prior. And now of course when I reflash the PCM with a tuner I'll have the current stock software stored to reload if I want to return it to stock instead of outdated software. Under $300 for a full vehicle inspection, PCM reflash, trans service and band adjustment and a new Dodge key fob programmed for the keyless entry. Man did I get screwed. I wish I was "knowledgeable".

 

[rkressg]

There was an issue many years ago with defective/failing oil pressure sensors in these trucks. I can't remember the TSB, but I am sure a little searching can find the number.
The flash changed the PCM to report ~60 PSI of oil pressure any time the engine was running. It was a specific flash if I remember correctly, that just addressed the oil pressure.

The real fix involved replacing the Oil Pressure Sensor (which is about $80 from Cummins).

The oil pump on these engines is gear driven, and basically, as long as there is oil in the engine, and it is turning, you will have oil movement and pressure. I would guess this is why Chrysler did the software change, as it was less expensive than replacing the sensors on all the trucks. About the only way not to have oil pressure is to not have oil in the engine.

 

[CM_Guest]

Unless there's on the suction side of the oil pump preventing it from pumping or a downstream leak dumping pressure oil before it can get where it needs to be. There's no such thing as guaranteed oil pressure.

 

[Wayne M.]

I think he's trying to say that no oil pressure in a buzzing B is like not having a high tide on the ocean. Now CJ, you might not believe this but if you're talking about your '02, the oil pressure as seen on the instrument panel is a "factored" reading. It's not true oil pressure.

 

[jgillott]

There was an issue many years ago with defective/failing oil pressure sensors in these trucks. I can't remember the TSB, but I am sure a little searching can find the number.
The flash changed the PCM to report ~60 PSI of oil pressure any time the engine was running. It was a specific flash if I remember correctly, that just addressed the oil pressure.

The real fix involved replacing the Oil Pressure Sensor (which is about $80 from Cummins).

The oil pump on these engines is gear driven, and basically, as long as there is oil in the engine, and it is turning, you will have oil movement and pressure. I would guess this is why Chrysler did the software change, as it was less expensive than replacing the sensors on all the trucks. About the only way not to have oil pressure is to not have oil in the engine.

I think this is the one from years ago.

09-001-01
1/19/01

Intermittent loss of oil pressure sensor ouput voltage.
This bulletin applies to 2500/3500 diesels with engine serial number 56744083 to 56809910. The
output voltage of the oil pressure sensor may intermittently dropout. This condition may cause
the engine oil pressure gauge needle to erroneously indicate lower than actual oil pressure. A
warning chime may sound and the “Check Gauges” lamp may illuminate. The Engine Control
Module (ECM) software has been revised to address this condition. Replacing the oil pressure
sensor will not correct this condition.

Do you remember how many of those sensors we replaced for a while? I think the guys up at Cober got sick of seeing me after the number of times they ordered them in for us.