So i just bought my first mustang about 2 months ago. Its a 96 mustang V6 automatic. everything is stock. the odometer is broken (stopped working at 138,000) and the owner says it has about 150,000 miles on it...

Anyway, i have this weird problem. everytime i drive the car for about 20 mins or so, when the car is idle, the oil pressure gauge starts to drop below normal. The longer i drive, the further it drops when idle. When im cruising it goes to normal again.my neighbor told me that it isnt my oil pump and he replaced the oil pressure switch. He's stumped now. what could it be? could it have something to do with my odometer problem? help!!

 

My gauge started doing that years ago, sometimes it reads fine, others it can be 0. Kinda bothered me at first, so I replaced the sender (twice) no difference. When I connected a manual gauge it read fine. Knowing that, I just ignore it and keep changing my oil every 3000 miles.

Advice, hook up a manual gauge and ensure you have acceptable pressure.