Had an issue with my oil light coming on when the revs dropped below idle. Only when the car was hot though!? After the car was real hot it would stay on at idle only. Well after researching it a little i seems as though I'm not the only one with this issue.

I got the part number for the oil pressure switch(sender, sensor or what ever) from evo general and bought it from the local dealer for 16bucks. Put it in and its fixed!

I wanted to make this thread because it was a little hard to get the info i needed after searching. I think this thread will make it easier for the next guy so,

Use silicon gasket sealant on the threads to keep it from seeping out. (~$3)
The oil pressure sender part # 1258A003 (~$16)
I also found that using a 1 1/16 deep socket on it made it real easy to take it out and put it back in.


Here is where it is.



Hope this helps some one.
BTW my car is a 05 VIII MR w/15k on it!

 

I just ordered a new sensor through JNZ's OEM system and that part number pulls up the sensor for a base Lancer, not the Evo. Maybe they have it wrong, but it looks legit.

 

where's the oil sensor located? is it by the oil pan (passenger side) or is it located on the driver side?

 

Drivers side back of the cylinder block towards the top. You can reach it easily enough with the UICP removed.