I have a 02 f150 4.6 v8 4x4 oil got a little low the other day light came on had to add some then on the way home it came on again checked oil was good cranked back up pressure back good then pulled up at home pressure dropped again turned off then back on again pressure good. Week later when to town light was on all the way thur town then back on pulling in drive way herd a slight ticking noise while light has been on then turned truck off checked oil was good cranked back up pressure when up normal and noise stopped. Any idea was causing the low oil pressure fluctuations when I have oil and the noise after a while of driving with the light on but goes away once the pressure goes back up after I turn truck off and back on again

 

How many miles? What grade of oil are you using?

 

Maybe a bad oil filter or faulty oil pressure sending unit.

 

Truck has 218000 motor has about 100,000. And just replaced oil filter housing couple months ago replacing the oil sending unit and broke it so it has a brand new one on it and using 10w-30 living in eastern NC here

 

What brand of sending unit? It's just a switch that actuates above a certain pressure. The oil might be on the edge for viscosity and the pump's not pushing enough to actuate the switch. Does it happen when the engine is cold or only when it is hot?

It's a one pin switch so it uses the threads/sender body for ground. If you used Teflon tape it might be losing its ground. Might be worth a shot to give it another half turn with a wrench. Looks like Motorcraft is still available.

https://www.rockauto.com/en/moreinfo...t=4588&jsn=659

 

Honestly it can happen at any time and idk the brand I used and we used teflon tape but we replaced it back about 4 months ago and never had a problem until I ran out of oil the other day by accident that’s when we started having problems

 

I have an autozone sending unit in my Mustang that only has about 500 miles on it.... and it is bouncing around. Oil pump and pickup are brand new, I know it has pressure. It's just a junk piece of garbage sensing unit. I need to just get a Motorcraft and be done with it.

 

white89gt - you are around and helped many. Is there a reasonably easy fix to replace the dummy oil pressure fix (in F150s) so we have a pressure sender and more realistic OP gauge???

 

I'll have to see if I can find his thread, but @OhioLariat actually made his a working gauge with a kit he bought. Let me dig around and see if I can find it.... otherwise, I am sure he can help.

EDIT: That didn't take me long.... here you go: https://www.f150forum.com/f6/oil-pre...k-real-422226/

 

If I could add a topic to the discussion, while it's hot - I keep getting a code for the oil pressure sensor (I forgot the exact code) which says something to the effect of "this code may not be real so clear it and try again" right in the description. It's come up 4 times or so. It never trips a CEL and I've never noticed the gauge behaving strangely.

Just keep clearing it or replace the sensor?