I have a 97 F150 with 4.2L and the oil pressure gauge bounces after the truck has ran for a while........it only bounces when i come to a stop....no engine noise at all.......then when i accelerate it goes back up to where its supposed to be. Then sometimes the gauge will bottom out. I have changed the oil sensor and still does it. ANy ideas?? is the engine toast?? is it the oil pump??
anyone with a good idea please lemme have it. Im thinkin on changing the oil pump...............but dont want to pop the engine out......thanks for all the good answers and this great forum. Helps me troubleshoot my truck when need be.
Deeerhunter04

 

Temporarily install a mechanical oil pressure gauge. Just run it to the cab through the firewall and watch the pressure. Could be the indicator in the cab rather than the pressure.

Search for other posts/threads concerning oil pressure; I wouldn't consider the OEM gauge as a reliable source. There is one person who has a "real" oil pressure gauge; search for that thread also.

Best of luck.

 

deerhunter what did you find out. I too have a 97 f150 4.2l and am in the exact same position as you. the thought of having to lift the engine just sucks. but maybe inevitable.

 

Replace the oil sending unit.

 

did anyone check the oil level? when you go around corners/up hills,etc.. when the oil is low and the pickup goes dry then you have a air pocket in the pressure line that sends the signal that you have no oil pressure and the guage falls to zero...or a faulty filter is suspect...zap!

 

well dam, ford oil pressure senders move eh? mine only moves when I start it up and turn it off lol

 

i used gunk engine flush changed sending unit and put new oil and filter on and that seemed to do it.