What does this sensor do on a 12 valve. There really isnt aything that can be controlled by the diffrent temps is there? The reason I am asking is the PO unplugged it for some reason and now I cannont find the plug. I have found a few cut wires. Does anyone know the wire colors as well?

 

I'm not sure what it does eather, but was told that, it is whats causing my oil pressure guage to go goofy!! At an idle, the needle drops to 0 and the check lights come on... I was told the intake air temp sensor was bad.. does your truck do anything like that or anything adnormal?? I'll check the wires for ya tonight!!-Chris

 

I have no idea on the oil gauage. My stock sensor has been replaced with a mechanical. It's amazing how much more they fluxuate and how much more pressure they throw tha the stock sensor says.

 

I think it tells the PCM to activate the grid heater cycle. It's one of the first sensors to test in the section on the grid heater circuit in the Haynes book.

 

So if it were to be unplugged then your grid heaters would never cycle would they? That makes sense because I cannot get mine to work.

 

My truck was doing the same thing. The previous owner replaced the oil pressure sender, but that didn't work and he gave up and just installed a 2nd mechanical OP gauge. Assuming your pressure is OK, there is a TSB that will basically turn the gauge into an "idiot light" to keep the annoying chime and check gauges light from coming on. In fact, my truck is having this TSB done today.

http://dodgeram.info/tsb/1999/08-22-99.htm