YAY! (sarcasm) Just put @ $1000 into my WJ for tires and a new..yes I bought a brand new...resonator box and today my oil pressure gauge went crazy. Looks to be the oil pressure sensor (whatever the little bit above the oil filter is anyway) but I'm not 100% sure about it. I'm fairly certain though.....oil level is perfect, I'm due for a change within a few hundred miles but not overdue, and I am using a extra capacity filter, 5w-30 penzoil high mileage oil. The gauge went haywire yesterday once, then this AM while finding a parking spot at work it did it again, always around low idle speeds (500rpm due to an existing vacuum leak I'm about to fix when the part comes in). But when I left this afternoon, every time I would round a corner at low speed and low (500 or so) rpm the oil pressure gauge would dip down to midway between 1/2 and zero and eventually to zero if I didn't give it a little gas to up the revs. At a stop light I had to hold one foot on the brake and the other on the gas to keep the revs around 800 or so OR put it in neutral and keep the revs about 800 to keep the oil pressure gauge from dipping down. I have never had this problem prior to yesterday's once before today when it did it ALL the time.
Searching the forums leads me to believe that I'm probably going to need to replace the oil pressure sensor (the one just above the oil filter on the 4.7V8) but it still scares the holy jeebus out of anyone.