I have a 01 Screw Lariat, 5.4. A couple of days ago I started the truck up and ran for about a minute when the oil pressure guage went to 0 and the light came on. I hurried up stopped, turned the engine off. I started it back up and the oil pressure came right up and has been normal until today. I started the truck this morning for work and when driving about a minute later the same problem happened, but before I could get the truck turned off it went back up to normal, happened two more times after that with the same result and then fine for the rest of my one hour drive.

Outside air temp was 39, checked oil level and it is fine, last oil change was 3500 miles ago.

Any suggestions????

Thanks

 

Sending unit going bad. It's just a simple pressure transmitter and your oil pressure "gauge" is nothing but an idiot light with a needle instead of a light bulb.

Don't know what they cost but I can't imagine they're too expensive. You could get a new one and swap it out if this keeps up. For me, this would be a prime opportunity to install a real gauge if it matters to you. You could also go buy an el-cheapo Autozone gauge and temp install it just to watch the pressure for a while to make sure it actually was a glitch with the old pressure switch. Installing a gauge (at the engine anyways) would be as simple as installing a new switch for that purpose. Run it for a while and then re-install a new switch when you're ready...or just go with a new switch to begin with depending on how **** you are

 

Thanks for your help, it seems like a pretty easy fix.

Looks like the oil pressure switch is around $10-$20 bucks. I would imagine I could do this myself. Is there any special instructions for doing this, and where is it located?

Thanks

 

The sending unit is a common failure, and a snap to replace. It'll be mounted on the oil filter housing, and takes a 13/16" (IIRC) wrench to remove.

 

When I go purchase the part do I call it a sending unit or a oil pressure switch, or is that the same thing.

 

They're the same.

 

i have more or less the same truck, 01 supercrew 4x4 with a 5.4, and the same problem it seems. on cold morings, in MS thats anything bellow 60 degrees, if i crank my truck up and throw it in gear the pressure drops to nothing. if its warm in the morings it doesnt have this problem. also if its cold out and i let it idle for about 2 minutes or more the oil pressure will not drop. ive heard it can be caused by not using a motocraft filter, i use a fram high milage. does this sound like a bad oil pressure sending unit as well? any help would be great.

 

01 f150 4x4 long bed 53k miles. My truck has been doing this the past few days when it has been cold out. It didn't start doing it until I had the oil changed. Could the oil be too thick or is this most likely a sensor problem such as above? I turn the truck on, the oil pressure drops. I turn the truck off then back on and everything is fine. Any suggestions?

Thanks