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'99 Mercury Tracer oil pressure light

The oil pressure light in my '99 Tracer came on two days ago. My husband changed the oil yesterday and disconnected the battery to reset the sensor but the warning light did not turn off. He assures me that the car is safe to drive but I am worried that I’m about to fuse the engine block. I did drive it to work this morning and notice that the light turns off when I accelerate from a stop but comes on again as the car shifts into higher gears. It does not turn off as the car downshifts. The pressure light did come on in February and he replaced the oil pressure sensor entirely at that time. The car’s performance does not feel any different to me.



Does anyone have an idea as to what could be wrong? The only repairs this vehicle has needed in 9 years are the A/C compressor 7 years ago and the oil sensor.

At this point, I have to say that your knowledge and/or instincts seem to be better than your husband’s.

Since replacing the oil pressure sensor did not resolve the problem, it is very important to have the oil pump pressure tested immediately. If hubby is reluctant to do it, then take the car to a competent mechanic. While damage may have already been done to the engine’s bearings, the sooner that this is attended to, the sooner you can stop further bearing damage.

That light is coming on because the oil pressure is reading too low. When you’re accelerating from a stop, the pressure increases because engine RPM does; then you settle into higher gears, RPM drops, oil light comes back on.

An oil pressure gauge needs to be hooked up (ideally in the same location as the oil pressure sensor) and the pressure should be checked at various RPMs. A reading that’s low enough means a faulty oil pump and/or worn bearings.

Oil pressure sensors and the warning lights they trigger do not “reset”.

Schedule a visit with a shop and get the pressure tested. ASAP. It would be far better even to have the car towed there…

How long ago did you have the oil pressure sensor changed? Can you elaborate?