I have a 2000 F150 4x4 with a 4.6L engine with 43000 miles on it. When I first start my truck in the morning my oll pressure drop to zero. If I rev the engine the pressure goes back to normal. This happens 4 or five times but stop after about 3 minutes of running. This only occurs the temp is between 32 and 45 degrees. This only occurs when I start the car after it has sat all night. It never happen later in the day, for example when I start my truck at noon. Any Ideas? ~ Phil

 

probably just a problem with the gauge. Supposedly they're not accurate for anything.

 

Welcome !!
Special Service Message #14907 1999-2001 F-150
~symptom=cold engine oil pressure reads zero or low~
~repair=install 1U5Z-9278-DA oil pressure switch~

 

The guage is not a real presure guage as it never goes up or down when working normal yours has gone bad now would be a good time to put a real presure guage in.

 

Is there a sensor that will make the stock guage fluctuate properly with changes in oil pressure?