Porsche-O-Phile

Used to be when the engine on my 951 got nice and warm it would indicate about 1-2 bar at idle. Last several days I've noticed it immediately pegs to "5" and stays there regardless of idle speed or temperature. The gauge DOES drop to zero when the engine is shut off (but electrical power still on).

What you guys think?

OPRV or oil pressure sensor? Any other thoughts on what to check?

How to verify one or the other?

Thanks.

Clint's 944

When it happened to me...it was the Oil pressure sender. It would shoot so high sometimes when I would turn the car off it would stay at 5 bar until I tapped the gauge!

Serge944

Make sure both wires have a clean connection on the oil pressure sendor.

It can't be the OPRV - hot oil can't have such high pressure at idle.

Gator_86_951

Jeff, I too had a sender issue on mine. Replaced it an it worked fine after that.

Porsche-O-Phile

Thanks guys. I suspected the gauge too (and I'll check the connections) but I don't want to be one of those guys that taps on the gauge and blames it anytime it doesn't tell me what I expect it to see (that's why they're there!!!) Kinda' like looking at the altimeter unwinding quickly and saying "geez, that can't be right. . . Lookit this stupid altimeter - it's busted!" before plowing into the ground.

M758

Sender problem or wire problem.

No signal from the sender pegs the gauge at 5 bar all the time.

Eyal 951

Jeff, you know it wasn't my sender. F*cked oil pressure party at my house! I have a spare oil pressure sending unit, and OPRV. You can try both and see if they help you. While your here, you can help me fix my high oil pressure, which is none of the above. (help!)
~Eyal

Porsche-O-Phile

Dunno - the oil system is pretty simple - not too many parts. Maybe a blockage at the return? I'm up for helping you chase it down of course, but it's shooting in the dark if you've changed the OPRV and sender.

BTW you have the 1-piece (new) OPRV ***'y or the older 3-piece one? If I'm going to bother doing it I suppose I'll upgrade.

89AZ944

I had exact same issue with mine.....except P.O. had reversed the wires in an attempt to fix it....

It was a bad sender. IIRC if it is a bad gauge, then the needle will peg as soon as you turn the key (before you start) and remain there until you turn the electrical off.

Porsche-O-Phile

Nope, that's not what it's doing - when you turn the electric (including gauges) on with the key but the engine is not running yet, it indicates zero. Once the engine starts, it jumps right up to 5. When you shut down the engine but electric is still on, it goes to zero again. I'm still thinking gauge, but want to be sure.

Eyal 951

i dont have the 1 peice conversion for 86, i sold it a couple months ago. sorry! but i do have a sending unit.
as for my car, I have two possibilities before I pull the motor for the pressure issue. Either mis-aligned oil cooler housing (could be, I've been in there before) or the slightly damaged oil cooler is affecting it. either way, i got the parts. Can you help this weekend? bring the engine stand, and I'll get you your cam tower back too!
~Eyal

Porsche-O-Phile

Yea I'll see if I can swing by. Who knows. . . Maybe I can dig through your parts pile while I'm there too. . . Mine isn't quite big enough to fall over and crush me yet, so I have to keep adding.

The DareDevil

Mine shoots up to 5bar as soon as I turn the ignition on. I'll try cleaning the contact on the sender unit before replacing anything.

docwyte

Mine sits at 5 most of the time, but at hot idle it'll be around 3... I may try cleaning the contacts on the wires/sender and see if that does anything.

BeerBurner

Mine recently started doing the same thing, and I figured it was the sender as well. But I have a question: does the idiot light work off the same sender? I won't be in a huge rush to replace the sender if I still have that light to warn me if it's about to die.

Oh, and my connections are perfectly clean and shiney, so I'm pretty sure they're fine...

BB.