Oil Pressure reading High: Mismatch between sending unit and gauge?

[Veronica87911]

Daisy is my 1972 911T, but has a 1977 2.7l engine.
I recently had a bunch of work done, and now the pressure gauge constantly reads 140 (not a "bar" gauge)

(the engine is not on in the photo).

think there might be a mismatch.
The new oil sender in the car is PN 91160611102, for 1977. I believe it should be PN 901-741-551-02-M100, for 1972.
Is this correct? Sorry for my silly question, but I'm knew to long hoods and mutts!
Thanks in advance for your help.
Serge

[lkadams]

Serge,

I don't have a ton of advice, but I think there are 80 psi senders and 150 psi senders. The sender needs to be matched to the gauge.

Best,
Keith

[edmayo]

Look at your invoice for the work. Was a new pressure sender included? If not, was the engine removed? If so, look and see if they attached the wire to the pressure sender.

[jrbennett]

Like Ed, I'm guessing the wire is loose or disconnected.
Does the gauge read 140 with the key on and engine not running? If so you have a wiring problem.

As Keith mentioned there are 2 different pressures available, however I believe both the part numbers you listed are for a 140psi gauge. The 80psi was used on '80s Carreras.

If I remember correctly, the difference between the "901" and "911" part numbers is the size of the threads on the sending unit (10mm on the "901" 18mm on the "911")

[Veronica87911]

Thanks for the info here and on Pelican; the consensus is that it is the wrong sender and I need to use one to match the gauge. I love the knowledge here.