Is their any way to just bypass, or do away with, or trick the ECM into thinking the oil pressure sensor is getting a good reading? The reason I'm asking is because I have a 99 CTD, and it has a bad oil pressure sensor, but I cant just go simply buy a new sensor to replace it, because cummins decided to go to a 1 wire oil pressure switch instead of the 3 wire sensor, and if I replace it with the new 1 wire switch I'll have to get my ECM recalibrated to accept it. I have a mechanical gauge anyway, so I don't really need some piece of crap switch to shut down my engine for me if I lose oil pressure. Seems like their should be a way to jump the plug for the sensor with a resistor or something to make the ECM think you have good oil pressure.

 

Never heard of such a thing.......Yours ( as a 99 ) shouldn't be a one wire switch anyhow......Even though you think it is a mechanical guage, it isn't. The instrument cluster decides what it is going to "show" you based on time running, engine temp, ect. It is a "calculated" number, far from being a real guage. Been that way since 98.

 

Why don't you read my post again.......I know I don't have a 1 wire switch. I have a "oil pressure sensor" not an "oil pressure switch". My "oil pressure sensor" is bad. I cant get a replacement "oil pressure sensor" because they replaced them with an "oil pressure switch". I have to buy the 1 wire "oil pressure switch" with the harness they include to convert my 3 wire plug to a 1 wire plug. When you convert to this 1 wire plug you have to recalibrate your ECM to read it, which is what I don't want to have to do.

I don't "think" I have a mechanical gauge, I "know" I have a mechanical gauge because I installed it.....It has numbers and everything.

 

Is your oil pressure guage something in addition to the factory guage? The factory guage gets info from the CCD bus system, and the instrument cluster then determines what to have the oil pressure guage read.

5012991AD - $217 Direct replacement

Where did you get that information? I can't find any TSB's, or Narrative in the parts section of the DealerConnect website referring to anything like that.........

 

I installed an actual mechanical gauge so I could get a real reading.

Is that part number for the sensor or switch?

Here is the TSB number I have 3377931-01

 

I guess what I need to know is how the sensor measures the oil pressure. On the orignial 3 wire set up, there is a +5-VDC supply wire, a signal wire, and the return wire. Basically I'm thinking if the sensor uses resistance in ohms to get its reading for pressure, then I could just get the right size resistor and wire it in between the supply and return wire to trick the ECM into thinking that oil pressure exists. I can't find anywhere that tells me what the readings should be for the sensor at different oil pressure levels. I don't know if I'm on the right track, or if this is just wishful thinking, but it seems like their should be a way to eliminate relying on a sensor, and just do it the old fashioned way and keep your eye on the gauges.

 

Where did you get that TSB # ? It doesn't look like all the other TSB #'s I've seen. Usually it would be something like 18-037-05 . I see what you are getting at as far as tricking the PCM now. The above number is the sensor # . Pretty salty, if you ask me! I can see why you wanna do away with it! See if there are any more numbers on your TSB, and I'll see what I can find as for as resistance readings.

 

Everything that I find says you already have the 3 wire sensor on a 99. The oil pressure sensor is on the left front of engine right above the ECM. Just want to make sure we're looking at the same part. I don't see an oil pressure switch available.

 

If I understand him correctly, he doesnt have a pressure switch. Cummins only offers switches as a replacement to his sensor, because the sensors are no longer available.

 

I got that TSB off of the Cummins Quickserve website. I have my ESN registered there, and I can pull up all sorts of info and bulletins pertaining to it.

So where can a person purchase that sensor still? I didn't think it was available anymore?

I was trying to figure out a way to post a link to the TSB. Here it is, but don't know if it will work. https://quickserve.cummins.com/qs2/p...n/3377931.html I can email the page to you if you want to take a look at it.

 

Link doesn't work for me. email it to andyjeep@hotmail.com
The sensor I lookes up came directly from Dodge. It has changed numbers ( and PRICE!) several times. It started life as only costing $77. It is still referred to as a sensor by Dodge.
I'm not trying to argue, just trying to help! I have access to all the Dodge info......I'm wondering if the Cummins info could be for another application. To the best of my knowledge, Dodge's PCM and the Cummins ECM, won't shut off the engine due to low oil psi. Are you just trying to make the guage read somewhat normal and keep the "dinger" from driving you nuts?

 

I'll try to email it to you. This is probably different than the Dodge pickups. This truck is a 99 Ford F800. It doesn't totally shut the engine down, but the warning light comes on, and it de-rates the engine so you don't have hardly any power. I called a cummins parts place, and the guy told me that the old sensor isn't available anymore. The new oil switch is $10, and the new cable adapter is $29.

I just looked at the bulletin again, and it said it does not apply to ISB engines installed in Dodge truck applications. Dodge trucks (model year 2001) and earlier will continue to use a pressure sensor.

I wonder if the pickup sensors are totally different then? The last part number I can find on my old sensor is 3408428, which is a cummins part number I believe.

Thanks for the help.

 

You could try the Dodge part, but without having one in front of me, I'd almost bet it is a Dodge part number. Probably different that the Cummins number. May be the same specs and all, but without buying one and comparing the resistance, gonna be hard to tell for sure. Easiest way I can think of - Does your sensor work at all ? Try to get a resistance reading off of it. Then go to Radioshack or comparable store and buy a variable resistor that will go both higher and lower that the reading you got. Play with the resistance until the guage reads where you would want it to. Cheapest way I can think of.

FYI - Next time, give all the facts......My bad for assuming, but this is a predominantly Dodge CTD website.

 

Ya, that might be the best way to go at it. I was just hoping maybe someone else had tried it before. Mine doesnt work at all. Do you have any specs off of a dodge sensor so I might have a ball park to begin with as far as a resistance range?

 

Maybe its a Ford part. I would check with a Ford truck dealer. It may not be the same or function the same as a dodge system