Oil Pressure Problems with 2002 Explorer
 

I have a 2002 ford explorer with 70000 miles on it. The problem I am wanting to see if anyone can help me with is that the oil pressure occasionally go from normal to no pressure imediately. Then within a minute it pops right back to normal. It has happened when I first crank up and sometimes just going down the interstate at a normal speed. My fear is that the oil pressure is really gone and there is a pump problem but with it either working or not I fear it could be a sensor problem. Any insight would help if you have seen a similar problem.

My GUESS (and it's only that, a guess) based on what you said, "within a minute", would be that your oil pressure is OK. Running zero oil pressure under load for anything more than a few seconds, especially repeatedly, would cause severe and noticeable engine damage.

I'd check the wiring to the pressure sensor for corrosion, that sounds the most likely problem. When sensors fail, they usually stay failed but broken wires and/or bad connections pop up and fix themselves repeatedly as the vehicle moves along the road or as the engine shimmies in it's mountings.

Can you reproduce the problem? In other words could you say to somebody "here, I'll show you" and make it do it more-or-less on demand?
If so you might get some peace of mind from a regular screw-in pressure gauge. You can buy one from any auto parts store such as autozone and prove to yourself that the pressure is good.

Hope this helps.

Fixed
 

I changed the oil pressure sensor for 12 dollars and it works like a champ.

Great, glad it worked.

How difficult was it to change the sensor? I have a 2001 Sport Trac that is doing the same thing. I am confident that the sensor or switch is going bad but I have no idea how to get to it. Where did you get the sensor, Ford or after-market store? Any insight would be appreciated.

Low Oil Pressure
 

I have an 02 ford Explorer V8 - About 8 months after I bought it I had about 82000 miles on it and the motor blew up. Once or twice a "low oil pressure" messaged had popped on for a few seconds and then went away. The oil pressure gage during the message showed no oil pressure but when the message went away, the oil pressure was normal (somewhere near the middle) I replace the motor and now 3 days after having the new motor the same message is popping up. My husband originally thought it was the oil pump going bad that had caused my motor to blow... the oil pump being built in to the motor made for a hard replacement. When I got the new motor (long block) it came with a new oil pump so you could imagine my dismay in seeing that message again. I am glad to see that the pressure switch is a common problem because my mechanic says the pressure switch is not located directly on the motor and had yet to be replaced. It's a cheap fix but a very important one. He thought maybe he bumped it during re-installation but a quick look under the vehicle showed no oil leaking around the switch it has just gone bad... I will be replacing it this afternoon and will report back in a week or so to let you know whether this was a permanent fix... Thanks