EL Fairmont Ghia oil pressure problem
G'Day guys and girls,
I have a 96 EL Fairmont Ghia which has had one minor problem since I bought it.
Upon startup, the oil pressure guage rises nicely to approximately half way up the guage and stays there.
Once the engine starts to warm up though, it starts to creep down.
After a trip down the freeway for example (about 45mins drive at 110km/h) the guage will be sitting a little above the warning area.
Once I get off the freeway and stop at a set of lights, the guage dips down to the warning and the buzzer goes off.
If I rev the engine, or drive away from the lights, the pressure goes back up again out of the warning zone.
I have tried this with 10-30W oil, as well as 15-50W oil.
Only real difference is local driving. The thicker oil just takes a bit longer for the warning buzzer to go off, but it eventually still does when idling.
I've been told multiple things from just a bung switch, problem with the pickups, all the way up to stuffed engine.
The fact it only occurs after the oil is warmed leads me to think it may not be a small thing like the switch, but rather the pickups.
I've had the car for 12 months now, and apart for some minor electrical work, this is the only real "problem" I've got.
Has anyone else had the same problem, or know what may be causing this ?