Oil pressure switch/gauge

[fizz911]

My oil pressure gauge immediatly when the ignition is on goes to maximum and stays there without altering. When ignition is switched off, the needle stays at max for about 8 seconds, then drops like a stone to zero. I have disconected the feed wire, expecting no reading from the gauge, but this has no effect on the problem. Have bought a new switch, but suspect after this test, no point in bothering to change.
Advice please. Thanks. Phil.

 

[chas3.2]

Hi Phill
Fit the sensor to the engine first.

 

[fizz911]

Thanks, Might as well try it.
Phil.

 

[fizz911]

Thanks, do I need to remove the instrument? or can earth lead be accessed 'under dash', also if I need to remove the instrument, does it 'simply pull out'?
Thanks. Phil.

 

[bones]

First thing to check is the sender wiring to the right of the engine fan, all wires can sooner or later break from the constant intense heat in the engine bay. The sender is prone to fail eventually too as is the gauge but check the gauge last.

 

[fizz911]

Further to my problem....!
There appears to be 3 'Oil Sensors' on a 3.2. The One to the right of the fan, which is cylindrical/round, and one lower down, and to the left, both easily seen.

I have just purchased the 'third' one which I think is the one which I think works the oil Pressure gauge, part no= 911 606 230 00. This I have eventually found at right of center, at the back of the engine after removing the large rubber hose between what I think is on the fuel inlet manifold, this is going to be a lot more tricky to remove.

However, I have, on all three run the test of removing the live wire terminal. This makes no difference at all to the problem, which, to clarify, when switching on ignition, before engine starts, the oil pressure gauge needle leaps up to max and stays there without moving.
When I switch off, the needle stays at max for about 9 seconds, before dropping like a stone.

Fortunatly I am sure the engine oil pressure is good as I have done lots of mileage without prob's.

 

[chas3.2]

Hi Phill

The oil pressure sensor is to the right of the cooling fan and cylindrical // the oil temp is the one lower down same place // the oil pressure warning light is at the back of engine under the air filter houseing. As Phill Clifton says check your earths on the back of the gauge First????. It sounds like you have purchased the oil light switch sensor. The one you want is 911-606-135-00 £50.31

Charles

 

[fizz911]

Thanks Charles, and all.
I think I am now forming a good idea on how to proceed. Will let you know the results. Phil.

 

[chas3.2]

Hi Phil
So what was the cure??

Charles

 

[fizz911]

Am waiting delivery of replacement sensor, will advise when fitted.
Phil.

 

[fizz911]

Dear Charles, and all who responded.

NOW Fixed! It was the cylindrical sensor next to the fan after all. Looked difficult to remove, but I got a special spanner made locally to remove it, took about 2 seconds, and saved dismantling all the ancillary items etc.

If anyone wants to borrow this tool please let me know.

Many thanks to all. Phil.