It is difficult to tell where the problem lies. I would rule out the oil filter as that sounds like a long shot. My guess is that its the gauge. If you have an ohm meter put in on the 100-1K scale in in that range. Pull the sensor connector and start the engine. Now measure the resistance between the center pin and ground. If you are getting 80-90 ohms the oil presure is fine and it would signal a broken gauge. However, if you are not seeing this resistance then something in the engine is wrong. Whats the mileage on this engine?
87GT - with 3800SC Series III engine, 4T65eHD
87GT - 3.4L Turbocharged engine, modified TH125H
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