My 87 GT has an issue with the oil pressure gauge. After I drive for about 25 minutes or so once the car has really warmed up the oil pressure drops and the oil light comes on. If I give the car gas or put it in neutral the needle goes back to mid point and all is fine. I did change the oil pressure sensor emit long ago. Thinking about purchasing another one. Any thoughts????
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[This message has been edited by Fieromn87 (edited 03-30-2021).]
If you have a Fram oil filter get rid of it and try another brand. Any other brand!!
Spoon
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
You can pick up a mechanical pressure gauge at your local auto parts. It will usually have a nylon coiled tube and several fitting adapters to screw into the oil sender tube once the sender is removed. Best to check with a mechanical gauge so you will know if your sending unit and circuit are accurate.
A word of caution when removing and installing the oil pressure sender. You will probably need to remove the battery and the plastic shield to make access easier. Use a short adjustable wrench to hold the square upper end of the tube to prevent breaking it. Then with a 9/16 open-end wrench, turn the sender by the hex fitting underneath the sender. Don't turn it by the large hex area on the shell. It will break.
You don't want to break the sending tube. They are hard to come by and even harder to swap out while the engine is in the car.
This is a good call. I was going to say how do you know the oil pump is not failing?
I don’t know for sure. I had the car repaired at the fiero factory and he replaced the gauge. The car has 87,000 miles on it per the odometer and sat for awhile prior to me buying it.
How do you know that the engine isn't worn and the pressure really IS low once it warms up? Low miles?
Not sure. The car shows 87,000 on the odometer now. Had 86,700 or so on it when I bought it. I replaced the sensor with a BWD and was thinking it may not be the best. Jeremy at the Fiero Factory did some work for me and thought it may be a bad sensor.
Yes, check w/ a mech gauge because dash gauge often lies. I skip that above.
Can check dash gauge w/ resistors between OP gauge "pin" on sender plug to ground. see cave page. 0Ω-0 45Ω-1/2 90Ω-full scale
If sender is bad, upgrade to 88 sender.
any mech gauge w/ tube often needs longer tube to use in Fiero. Tubes can, often will, fail when pinched, sees high heat, and more. So If you see "0psi" then stop engine fast because tube fails will spray oil quarts of faster and if hits exhaust, a big Fire.
Good advice the one I bought was a BWD. What do you suggest for a much better brand? AC Delco???
I've had good luck with Standard or Echlin from NAPA.
When I use a mechanical gauge, it's only to test. I warm the engine up to operating temperature and let it idle to see what the idle pressure is. I've also used one of those large spring metal type paper clips to clip the gauge to the engine vent so I can glance back at it while driving to see what pressure I have at operating speeds and temps.
[This message has been edited by fierofool (edited 03-31-2021).]
