porsche_addict

I have some questions regarding the instrument gauges in my '86 951. When cold starting the engine the oil pressure gauge needle touches the '5'. After the engine has reached engine temperature, the gauge rarely drops below '4'. Do I need a new oil pressure sending unit or is there actually a cause to the high engine oil pressure? The fuel gauge does not register higher than 3/4, even when I've filled the tank to capacity where the pump has clicked off. Is there a more precise way to fill the tank so I can obtain a complete fill or is the gauge merely not accurate? Lastly, the voltage/ charging gauge reads 12 most of the time. On occasion it will move up half way between 12-14, but knowledge tells me it should be close to 14 at all times. Where can I begin to troubleshoot? What are the chances that it is something other than the alternator? Thanks.

porsche_addict

Anyone?

Giantviper

As for the fuel guage, from my experiance it is common that a full tank only reads 3/4 full. (I know of a lot of 944s do this and I do not know of a practicle fix)

For the oil pressure gauge, when under load it should read 4 or 5. Also when the engine is cold it will read 4 or 5. One the engine is up to temp it should read 2.5-4 when idling.

Also, I think the voltage gauge should read between 12 and 14 depending on how much electronic equiptment you are running.

I hope this helps.

Tom M'Guinn

I'd start by sorting the voltage. If the voltage is off, then the other gauges could be too. I'd check the voltage at the battery with a multimeter and compare it to the cluster gauge to see if the voltage is really low or if the gauge is off. If it is at 12 with the motor running, that is lower than it should be. If it is up between 13 and 14, yet the gauge reads 12, then I would check the grounds to the cluster. If you sort the voltage and still have the oil/fuel issue, then you'll have to go after those one at a time. (Change oil to 10-40; pull and check/clean oil pressure regulator; check voltage from tank sending unit, etc.)

bearone

oil pressure is fine, no.

fuel gage
http://www.clarks-garage.com/ garage shop/fuel shows the system and checks/things you can do

voltage should be upper 13's to low 14's running with a/c and lights on.

87951
95sl320 dd

V2Rocket

check grounds

oil pressure sounds ok, maybe try a thinner oil next change