I can run my car for about 5 minutes and the oil level indicator in the instrument cluster will slowly illuminate. It starts off very dim and then gets brighter and brighter at which point the buzzer will also start sounding. I have plenty of oil in the pan and very good oil pressure as measured on the factory and after market gauges. This is the second engine to display this problem within this car.

When I put a freshly rebuilt engine in, I also changed out the sending unit in the pan and now get the same results.

I don't know where to turn. I have a brand new sending unit I can put in. My other thought was that the problem is within the instrument cluster.

Any thoughts?

 

Could the problem be related to the voltage in the system?

When you start the car the starter would cause the voltage to drop and as the engine runs the voltage would naturally rise. The way the light starts out dim and gets brighter makes me wonder.

Maybe the voltage regulator in the dash is allowing too much voltage into the cluster.

 

A bad voltage could be the problem. I'm going to hook up another oil level sensor outside the pan and move the float to see what happens. If this doesn't work I'll try another gauge cluster.

 

My guess is it's gotta be the gauge cluster. How do the gauges themselves respond while driving? A friend has a recently gotten running 84-85 chassis and its oil pressure gauge goes to zero soon after it starts. It could be the connector being too oily inside. Check your oil pan wire.

Or your issue could be the multi-wire "bulkhead" connector in the engine bay. Try taking it apart and checking for corrosion on the "pins".

 

I checked the wiring from the oil pan to the firewall connector and this ohmed out good with zero ohms and had no corrosion. I've had the cluster in and out several times and have plenty of spares or I'll check that next.