wierd oil warning light & pressure light

[craigieeb]

iv got a weird problem here,
driving the car normaly every thing if totaly fine but, when iv given it a damn good thrashing about my oil warning light comes on ??? and to make things worse as soon as i get to 145-150 (kph guv) the oil pressure light comes on, so when i slow down (press the check button) pull over knock off the engine start it again everything is fine

iv checked the oil level and that's totaly spot on, and im totaly stumped on this one guy's, i'v been told it could be the oil thining out but im using semi-sinth oil,
so has anyone got any idea's to what could be causing this prob??

[sabrje]

If you are talking about the oil pressure light on the dash - mine did a similar thing - oil pressure light flickering as I put my foot down and again when I lifted off. Turned out it was the wire touching the fanbelt where it goes around the front of the engine. It might aslo be the sensor itself.

However, the oil level on the check control is different and I think it only checks the level before you start the engine (but I could be wrong) If your oil level is OK then its probably an electrical fault.

Could be something more sinister though - there's recently been a thread about what happens when the oil pump gives up the ghost so I suggest you find the root of the problem before you go any further

[craigieeb]

cheers for that mate, yeah the light on the dash comes on when im flat out @145-150 ish, and the check control for the oil leval come's on either just before or just after,
so do you think it could be the pump?
because if it was an elactrical problem it would be happening all the time yeah?
but when the car is driven normaly everything is spot ok

[sabrje]

As both lights are coming on I'd say its definitely somthing sinister as they run off different sensors. Get it checked out soon.

This is the thread I was on about.....
http://www.e30zone.co.uk/modules.php?na ... sc&start=0

[Brianmoooore]

The oil level sensor in post facelift cars has a static oil level sensor and a dynamic level sensor, and no obvious connection at all with the oil pressure switch.
If the oil level is up to the max mark on the dipstick, then unless you have some weird, unheard of fault, like the oil being held in the cambox while running, then the oil level side of things, at least, must be some peculiar electric fault. An engine which is low on oil doesn't refill itself when you stop.

[craigieeb]

An engine which is low on oil doesn't refill itself when you stop.

my thoughts exactly, which is why i find it totaly wierd mate, and the other only explanation i can come up with is the thining of the oil, its getting a total sevice at the weekend anyway so i'll see how it reacts with some nice new oil,

do you think it could be getting "held" somewhere in the engine??
and if it is why would it do that?
and what would stop it from doing it?

cheers : )

[Brianmoooore]

I suppose a massive amount of piston blow by could inhibit oil returning to the sump, but if it was that bad I think you might notice one or two other symptoms.
You haven't had any problems with the main engine earth strap at any time have you? If the main earth strap fails, the alternative earth path is through the brown/orange earth wire from the oil level switch. This causes a nice little burn up in the loom when you try the starter.
Check the oil pressure switch wire carefully where it runs around the front of the engine. Sheathing and wire insulation gets brittle from the heat, and the wire can come into contact with the fan pulley. Intermittent shorts here are fairly common.
Oil pressure switches aren't that reliable either. Try a fresh one before you get to deep into sorting this.

[Ade]

I got a similar thing with my coolant level check light last night. Thrashing it nicely down the M40 and when I slowed for the service station the coolant light came on...

stopped, checked the coolant level was still ok (it hadnt changed), wiggled the wires to the header tank, switch ignition on again and hey presto - light out!



Any suggestions or just dodgy wiring??