Oil temperature/pressure warning light on

[hernan gonzalez]

Hi,

I am new to this forum. Own a 1976 2.7 liter 911s. The car has some 60K miles and has always been in good shape. About one year ago, the oil temperature/pressure warning light started turning on when the engine warms up. It does not turn off even when revving up. When that happened the first time I looked at the pressure gauge and temperature, and given that the readings where OK, I did not give it a lot of importance. I have been using the car for almost a year since; however, it always worries me a bit, so in fact I have not taken it out as much for that reason; what can be the problem here? a sensor? is there a different one for the pressure gauge than the warning light? I'll appreciate any help

[dshepp806]

I would suggest getting the actual oil pressures measured...start there to establish no issues with oil pressure(s).

[hernan gonzalez]

Thanks for your answer. Actually, that is what I did first (sorry for not mentioning) after the warning light first turned on... wanted to be sure I was not going to ruin the engine. Pressure meassured externally was exactly as the pressure gauge, all fine

[86 911 Targa]

Originally Posted by hernan gonzalez

Hi,

I am new to this forum. Own a 1976 2.7 liter 911s. The car has some 60K miles and has always been in good shape. About one year ago, the oil temperature/pressure warning light started turning on when the engine warms up. It does not turn off even when revving up. When that happened the first time I looked at the pressure gauge and temperature, and given that the readings where OK, I did not give it a lot of importance. I have been using the car for almost a year since; however, it always worries me a bit, so in fact I have not taken it out as much for that reason; what can be the problem here? a sensor? is there a different one for the pressure gauge than the warning light? I'll appreciate any help

For our '86,

If it is the oil pressure warning light.

Page 970-78 of our Bentley, showns connections from the oil pressure light
to your dashboard warning lights. (E-brake, Pad sensor, and seat belt).

Are you seeing any other issues?

Good luck,

Gerry

[Walt Fricke]

Hernan

I had a somewhat similar issue with my '77 when it was new to me (though otherwise well used).

The warning light sensor is a spring loaded contact, with the spring pushing it closed. Pressure opens the contact, and it doesn't take much pressure - maybe 4 psi or so. The sensors are notorious for leaking. I suppose that if oil leaked into the top side, the spring could close the contact because the pressure would be about the same on both sides.

Otherwise, any ground in the wire from the sender to the dash light will cause it to come on.

You could check this path by running a long wire from the sender to the dash connection, partly outside of the car (temporary, just to check).

However, since it is hard to reach where the sender wire connects to the sender, I suggest you replace the sender while you are at it. They aren't super expensive, and don't last forever.

To do any of this, you might want to do a partial engine drop. Pelican has a tech article on this. (use at your own risk, I wrote it what now seems long ago). It is really hard to reach that part of the engine without doing something like this.

Your instruments, where the bulb assembly is located, just pull out of the dash, being held in by the friction of the rubber ring around them. If you can't get one out, try its neighbor so you can reach in and push the sticky one out.

Good luck

[hernan gonzalez]

Thanks a lot for your advice, I'll go ahead and work on it over the weekend...
Saludos, Hernán