I have noticed, although intermittent, when I start up in the morning, the oil press gauge raises to the normal reading, then it goes back to zero press (it lays down) and the low oil press idiot light illuminates. The gauge then goes back to its normal position, light extinguishes, then it starts all over again, repeatedly. I notice that if I increase the rpms' to 1500 this stops. Once the idle drops back to normal, it starts again. Once I drive, it stops, and once the truck starts to warm up, it stops. I park on a slight incline on my driveway and the dip stick reads that I could almost use a quart of oil. Even if I am down 1 quart, this should not make this happen, should it???

Thanks for all input
JB

 

check the oil when parked on a flat surface, add as necessary. If the problem still exists, I'd guess it is a bad sending unit. Easy to replace. It is on the lower left corner on the driver's side of the block. Remove the LF wheel unplug the connector and replace. Have some rags ready as you will lose some oil.

Bob

 

Could be just a sending unit. But also could be: a leak allowing air into the oil stream, a wire shorting out (unlikely in your case), a dirty pick up tube/screen, too thin of oil.....

I agree with Bob that would be the first thing to do along with a change of oil and filter.

Rich

 

My 2000 L started doing the same thing about 2 - 3 weeks ago when it was real cold weather. It doesn't do it all the time and only does it when the weather is cold along with the engine. The longest period of time it has stayed down is about 2 minutes when first cranked.

It freaked me out when this first happened. After a couple of minutes warmup it never does it again.

One morning it did this when I put it in reverse to back out of the garage. I put in drive and it swung back up. I put it in reverse and back down then drive with it going back up. Go figure. I have to change my oil this weekend so I will take a look at it then. At least it will be in the 50's.

P.S. The oil level is fine.

 

my truck did the same thing during the first cold spell we had.. it was the sending unit. i had it replaced under warrenty.

 

It is right behind the power steering pump on the drivers side. I just replaced mine last weekend. It would drop to "0" when the engine was cold and the weather was cold. So far so good and the weather has been cold for a couple of days.