Oil warning light won't go out !

[Wolfy]

Hi folks.

Half way to work today (3 mile each way) my oil light started to flash. It did it all the way home as well and seemed like it was losing power. I've left it to cool and topped up the water which was low and the oil which was not even showing on the dip stick, not sure how I missed that one. I've started it up again and it sounds ok but the oil light is still flashing. I don't want to take it for a spin to test the apparent loss of power until the oil lamp is out. Will the lamp stay on if I've over filled it or could I be looking at something else?

Any help would be much appreciated.

[Aidan]

ok what engine have you got ? crystal ball isn't working

and what year ?

[Wolfy]

That would help wouldn't it.

It's a 1987 1.9 watercooled.

Many thanks.

[Aidan]

so wbx late has 2 oil pressure switches, the low pressure one is closed when engine is off and once the engine starts and you have 3psi of oil pressure it goes open and the flashing oil light goes out, the other one is part of the bod system so that when you are pulling more than 2k rpm it checks you have more than 1.8bar oil pressure, if you don't then bod goes off, it switches the opposite way, ie is open engine off and closes when op is what it wants to see

the two senders have a single wire each which pair at a double connector left side of engine near the electrical connections box, if you disconnect this plug you can check what output you are getting with the engine off and running with a simple continuity check, thus low pressure will be closed engine off and open with 3psi, high pressure will be open and closed at 28psi ie idle stone cold or at higher revs when hot

if your low pressure sender isn't opening it suggests that you don't have decent oil pressure or the sender is faulty or there is a problem with the wiring

if the sender is working as expected then it's probably a wiring issue from that connector in the engine bay to the dash, needs continuity testing to find the problem

best thing is to remove pushrod cover, remove sender and fit a proper wet oil pressure gauge and see what the pressure really is, you'd hope to see 3-5 bar stone cold at idle and more than 1bar at idle hot, rising rapidly with revs to 3bar at 3k rpm, if you get these sorts of figures then it's definately a sender/wiring issue and you can stop worrying about oil pressure

if you haven't got 3psi then chances are you've done the crank bearings due to low oil

it should all be in the wiki

[ghost123uk]

Oil light flashing ? = I have not come across an oil light that flashes. Are you sure you're not looking at the coolant warning light ? (you did mention the coolant was low). Though if it was an irregular flash, that could have been the pump sucking up air due to virtually no oil in the motor.

And, you got a red warning light on and a lack of power, and you drove on to home. A red light means stop immediately or you will wreck your engine. To be honest, and I hope I am wrong for your sake, but, due to the very low oil level you mention, the lack of power might have been a partial seizure, which is pretty terminal. It might not be that though, it might be just a coincidence and turn out to be summat else.

How long was it since you last checked the oil level ? If fairly recently (weekly is normal) then there must be a reason it disappeared. Do you have any leaks or blue smoke issues ?

As Aiden says, the very first thing to do is get a wet oil pressure gauge on it (via the thread between the pushrod tubes on the lhs).

Oh, and no, the oil pressure warning light will not come on if you over filled it.
Did you over fill it ?

[kevtherev]

Oil light flashing ? = I have not come across an oil light that flashes. ?

IIRC The high pressure oil switch (I call it the main bearing pressure switch) will flash on a late.

well mine does