hey guys i got a question i can't tell if its just the idiot gauge or if i actually have some type of problem. I have a 94 5spd 4.9 litre f150 2wd. Last night i started it up and its been cold out and when i went to drive and stoped at a stop sign at idle the oil gauge started fluctuating pretty largely. I gave it gass and it seemed to level off again. didn't think much of it. but then today i went to go drive it again and when at idle again and even while driving gauge was still flucating quite a bit. Is this just becuase the guage is doumb or do you think i may have an oil pressure problem.
Thanks
Mitch

 

If the gauge ever rises past the normal area (around the "r" in normal) you have a short or something, since the gauge only reads two positions: red zone, and normal. It takes a bit to go between them, so if it starts to drop down at a stop light in drive, the lowest RPM's the motor will reach, your oil press is probably a little low. The "low" on the gauge is triggered below around 5-6 psi or so.

If it's fine during nomal driving then I wouldn't be overly concerned. If you're stopped in traffic for a while, just put it in neutral to raise the RPM's a bit.

You could install a mechanical pressure gauge and get a true reading if you want. Normal driving should read around 30-40psi, around 10 or so at idle.

 

If you do have a problem, like the oil screen stopped up, when the pressure drops, you'll notice the engine start to tick. First sign of oil starvation.