Hi,

My sister in law has a 2003 R50 with about 150K. Recently, the oil indicator has come on, however it will go away once the RPMs rise above 1500.

There aren't any knocking noises, but the temperature does go up slightly when the RPMs are low.

She has had the oil sensor replaced and has changed the oil/filter (thinking that the filter might be restricting flow). Neither of those efforts remedied the issue.

The car is parked now for fear of causing any damage.

First question...

Does anyone have an idea what might be causing the oil indicator to come on?



Second question...

If you believe it's an oil pump, how difficult is it to remove/replace the pump?



Thanks in advance for your help!!!

 

Typically the oil light comes on when the oil pressure is at 12 lbs or less so assuming the sensor is working properly since it is new then we know that we have less than 13lbs of oil pressure. Has the oil pressure slowly be declining or has it been a sudden change??

 

I don't know if the pressure has been declining. They only have the typical "idiot light" indicator which is either on or off, of course.

I was just told that the rising temps stopped occurring after the filter was replaced. The light is still on at low revs, though.

 

Double post. Sorry.

 

I would get a gauge of some kind on it to read actual pressure, if that read low, I'd pull the oil cooler and filter housing, there could be a restriction near the sensor.
If not I'd start looking at a pump restriction or bad pump/gears itself.

 

Has it has frequent and regular oil changes? If not, it could be that the bearings are worn and the old oil pump can't keep up to maintain pressure.

Hopefully it is something less drastic.

 

Was the oil changed recently? If the filter isn't seated correctly, it'll cause that light to come on at idle.

 

Go to Harbor Freight (or go online) and buy one of their oil pressure testing kits for something like $25. Hook it up to your motor so you can tell exactly how much oil pressure you have at idle. If your oil pressure it good at idle...it would be a problem with the sender, or the wires going to it.

Either way....don't drive it until you know what's going on.

 

Like he said we see this all the time with aftermarket filters. But if someone has damaged or removed the plastic part in the oil filter cap you will have the exact issue with the oil light. So I'd remove the oil filter and check this first before going any further.

 

Check inside the oil filter canister itself. There is a little black plastic spring actuated "valve" of sorts in there. I know this because in my 2005 Cooper S, it broke and did just what your oil light is doing. Unfortunately, you need to replace the whole oil filter canister to fix this issue. I posted about this somewhere on these pages a few years back.

 

I lied. I didn't post about it... thought that I did... Anyway, there is a black plastic valve thing in there and it can break.