1998 Plymouth Grand Voyager, 3.3 liter engine, automatic transmission, 125,000 miles
The low oil pressure warning light will intermittently illuminate. I replaced the sending unit and everything worked fine for three days, then the light started illuminating intermittently again. I removed the sending unit and temporarily installed an oil pressure gauge; oil pressure was 60 psig at idle speed and increased to 70 psig at 2000 rpm (engine was cold, using 10w-30 Mobil One synthetic oil). I thought that the replacement oil pressure sending unit may have been defective so I replaced the switch again; the light worked fine for one day and then started illuminating intermittently again. I have noticed that the light tends to illuminate more often when the brake is initially applied. The light never stays on for more than a couple of seconds.
I wiggled the wiring harnesses thinking there might be a short to the engine ground but I could not find one, could not get the light to illuminate while I was wiggling the wires (both in the engine compartment and under the dash).
The air conditioner compressor and recirculation lights also flash for about 15 minutes -- similar to what is discussed in another post (I think the unit was inadvertently placed in self-test mode and now I cannot get it out of that mode). This problem has existed for quite a while whereas the oil pressure light problem just started this week.
I checked the OBDC codes, nothing.
I noticed a recommendation in some of the posts to check the Body Control Module. If this is what I should do, how does one test the module?