Oil light?

[watty1974]

Hi there,

I am having a issue with my oil light on my 84 Mk1 GTI, for some reason it is always on, i have tried changing the sensors. i have also removed the clocks to check behind, and cant see any problems. This car is very rarely used, although i start it most months, due to this i removed the sump to check the strainer but this looks clear.

My question is would anyone consider replacing the oil pump whilst the sump is off? This little problem has me baffled me and any advice will be greatly appreciated.

Just to confirm there are only two oil pressure switches on this car? I am convinced that its not the oil pump, however i just wanted to be sure and thought i may change it just to be safe. The car has covered 110k with history so i guess it would be rare for oil pump failure.

I have disconnected the both senders / switches one on the left of the head and one on the oil filter housing and I'm still getting the oil light, however because the sump is off i cant start it, but i think even without those two connected i shouldn't have the light on at all engine on or off??

I think this is an electrical problem or the clocks maybe???

Sorry for all the questions!!!!

[Crasher]

With the engine not running, the oil light will flash but with the head switch disconnected, the oil light should go out. What colour is the switch in the head and the switch on the oil filter housing.

[watty1974]

With the engine not running, the oil light will flash but with the head switch disconnected, the oil light should go out. What colour is the switch in the head and the switch on the oil filter housing.

Hi Crasher,

I believe that are both white? With the head switch disconected the lights still on???

Thanks

[watty1974]

Sorry talking complete rubish, blue on the head white on the filter housing, i have read that it should be brown on the head, would thia make any difference?

Thanks

[Crasher]

Blue is the new brown and white is still white, blue/brown in the head, white on the oil filter.

[RJPeaker]

Hi,

I'm new to this forum and wanted to check if your problem is the same as the one I'm having. The oil light is fine unless the revs go over about 1500 rpm, and then the oil light flashes. Everything seems to be fine though, it's not overheating or anything, and the oil is the right colour. Is the same as you're getting?

Thanks,

Richard.

[Crasher]

You have a low oil pressure warning. What is the car, engine and year?

[RJPeaker]

Thanks for replying. It's a '84 GTi cabriolet so I think it's a 1600 fuel injected. I removed the lead from the sensor on the oil filter housing whilst the engine was running and the light still flashed, and when I removed the wire from the sensor on the RHS of the head (as you look at it) the light went out. Does this mean anything specific or is it a case of changing oil pressure switchs to see if one's broke?

Thanks for your help!

[Crasher]

If it is an 84 it should be an 1800, a quick identification is if the top hose outlet comes out from between cylinders three and four. The oil switch on the oil filter housing detects oil pressure above 1.8 bar (a white switch that closes with pressure) and disconnecting it will trigger the system. To temporarily eliminate it, you should earth the (yellow) wire and there should be a convenient earth tag on the distributor body.

The switch on the head (brown 0.3 bar, blue 0.25 bar pressure to break contact) works the other way around and if disconnecting it (blue/black wire) stops the warning, I think you have a problem.

You should stop running the engine now and either drop the sump and replace the oil pump or at the very least, have an oil pressure test done.

[RJPeaker]

Thanks for the info. It's dark now and the cars under it's cover so I wont get to look tonight. Are you OK with me asking a bit more advice when I get to check out what you've advised? Many thanks, Rich.