Intermittent oil light when driving

[richlaz]

Hello

I'm having a slight problem with my T25 (1984 1.9 DG)

When the ignition is on, the oil light comes on. Then when the engine is started, the oil light goes out, exactly as it should do.

Although when driving for 5-10mins+ the oil light will start to illuminate, but starting very dim, and eventually gets brighter and brighter. When driving I've also noticed that it intermittently comes on and off, but generally dim, hardly ever at full brightness.

Is this likely to be an oil pressure sensor? (done a bit of googling, not sure if there's one or two on the DG, and where are they?)

I'm hoping it's not the oil pump. Engine sounds normal (well as normal as a T25 engine can do!)

The oil level is ok, just under max.


Any advice would be greatly appreciated. Cheers, Richard

[AdrianC]

Is this likely to be an oil pressure sensor? (done a bit of googling, not sure if there's one or two on the DG, and where are they?)

Once you've ruled out the obvious - a bit of bare wire shorting somewhere in the engine bay - the quick and easy way to rule out the sensors is to disconnect them.

I dunno if yours has one or two - on our DJ, the low-rev sensor is under the LH cylinder bank. You need to remove the tinware hiding the pushrod tubes to get at it. The high-rev one is behind the water pump pulley. It's allegedly get-attable without removing the water pump pulley, but that was much easier than I expected. On ours, though, they both come to wiring connections around the front of the LH side of the engine bay. The high-rev wire needs to be earthed to tell the dash that the pressure's good, the low-rev one can be left loose.

If it makes no difference to the light flickering, your problem's somewhere in the wiring or dash.

If it does solves the flickering and coming on dim, then change the sensors. They're not expensive from BW. I dunno about the VW ones, but on other engines I've had pressure switches fail so that they pee oil EVERYWHERE, and I know people who've had 'em suddenly and totally fall apart emptying the sump everywhere, so they're probably worth doing as a precaution anyway.

If that still doesn't solve it, it's time to start investigating low pressure...

[richlaz]

Many thanks for all the info

Will have a dig around tomorrow if it's dry and see what I can find

Thanks again for your help. Cheers, Richard