oil pressure light

Evening.

So I've been using my series 3 2.25 petrol on a few shortish runs to pick up the dog etc. Its been running fine, occasional miss fire but nothing concerning.

The oil pressure light is now coming on and staying on. Previously it had flickered on at idle and then gone off as soon as the revs increased. I'd kept an eye on oil level but generally wasn't too concerned as it wasn't staying on.

However now its staying on I'm a little more worried and should probably stop driving it?

other than the obvious switch what should i be looking at? pump?

thanks for the advice as always

I had something similar 10 years ago when going on a day trip out, light came on at revs and stayed on, i drove back home, looked at pump, i wanted to check for wear or anything broken, its so long ago i cant remember if i changed the worn piston as shown, but i think a check on spring length was done, i also changed the switch and got a kit to plumb in a oil gauge and switch so i can see an actual reading, now i know a flickering red light is ok at idle and happy to see the pressure build up in normal driving.
it cant hurt taking the pump apart and seeing no broken spring in the pressure relief valve

If its not knocking, rattling and smoking I'd do the switch ASAP so you know, after that (as above) try the spring.

These old pumps are pretty robust, I'd change the switch first, it's the easiest and cheapest but I agree with steve2286w, an oil pressure guage is quite reassuring. I don't get the same pressure as Steve though, mine shows about 40 to 45 when cruising.
Col

Buy a cheap oil pressure gauge and fit it where the sender is...the see what it reads.

When I bought my present S3 50 years ago...one of the first things I did was fit an oil pressure gauge.

+1 on the gauge. Empirical evidence much more comforting.

Thanks chaps.

I’ll look at getting a gauge. Thoughts on electrical vs mechanical? Are there complete kits available these days. I’ll google.

Is the pump an easy job? Sump out?

Dan

I prefer mechanical...but may need an adapter.
Sump off pump is held on with 2 bolts I think...but what will taking it off tell you...you need to test its performance.

Oil pressure gauge doesn't have to be a permanent install...just used as a hand held tester with a temp plumbing job if req.

Thanks again. Will plumb in a gauge when I get a chance and see what readings I get.

I think you would be pretty unlucky to have a worn out pump on a petrol. The pumps used to wear on Diesels once the motor had done over 100k miles at which point I would steal the pump out of a completely worn out 2.25 Petrol and the diesel would be good for another 100k. Always amazed me that the rest of the Petrol engine would be completely worn out yet the oil pumps seems as good as new.

A 2.25 petrol will run on sheite old oil at minimum level for some time before complaining. As posted try the switch first.

A hint for anyone running a 2.25. Check the bell on the dipstick,it can come a little loose and slide up the stick a bit. The result is a stick that goes in to far and thern reads wrong, says it is full when it is not. Good idea when changing oil is to go on the measure not the stick.

Thanks for the tips and advice everyone. As always much appreciated.

Happened to me a few months ago so ordered a new pump just in case.

Finished work for the week and set to replace everything.

First thing I did was slip my hand behind the light and gave it a wiggle.

It went off. Seems it was a short


For sale. Series oil pump. Never fitted

Bobsticle said:

Happened to me a few months ago so ordered a new pump just in case.

Finished work for the week and set to replace everything.

First thing I did was slip my hand behind the light and gave it a wiggle.

It went off. Seems it was a short


For sale. Series oil pump. Never fitted

Click to expand...

YES! mine does this and its a loose bulb holder that earths and puts the light on ... i have to lift my instrument panel a mm or 2 and it goes out ...

I hadn’t actually considered the bulb/bulb holder to be faulty. Doh. I’ll check that too. Thanks.

How old is your oil? What spec is it? Mineral or synthetic? The older engines don't like any of this modern thin synthetic stuff, put a quality 20w50 or 15w40 in and see how it goes.

I'm using 20w50 mineral. it is due an oil change so ill do that too. Thanks

You can now get 20w/50 in semi synthetic or even synthetic as well as mineral