Oil light blinks at low rpm's dipstick says full.

[FordGtFan]

I just picked up a high mileage z4 and sometimes at traffic lights the oil light will blink a few times and then go out. Oil is full. Suggestions?
Thanks!

[Pelican Parts]

Hello and welcome to the forum! That's likely a short; check the fuses. Take a look at the link below to our site's DIY tech articles on the E85 platform. Please let us know if you have any questions!


http://www.pelicanparts.com/techarti...W_Z4M_Tech.htm

[dbarton62]

I just picked up a high mileage z4 and sometimes at traffic lights the oil light will blink a few times and then go out. Oil is full. Suggestions?
Thanks!

Could be a faulty oil level sensor which is in the bottom of the pan.

[GeorgeT]

I just picked up a high mileage z4 and sometimes at traffic lights the oil light will blink a few times and then go out. Oil is full. Suggestions?
Thanks!

The Oil Level light or the Oil Pressure light?

[cdsweet]

The Oil Level light or the Oil Pressure light?

That's my initial thought, could be improper viscosity oil used during last maintenance or oil change is needed?

[keeton]

You said "high mileage" but didn't quantify it. As the mileage accumulates, the engine bearings get, er, "well broken in" and there is greater clearance between the surfaces and makes oil pressure more difficult to keep up, especially at idle when the pump is turning more slowly. I'm guessing that this only happens when the engine is fully warmed up and the oil has thinned. The light is just showing momentary drops in oil pressure. If it is just at idle, I wouldn't worry too much about it. If the vehicle is otherwise running OK, the cheap solution is to use a thicker viscosity oil.

[MIKYZZ4]

Have ever replaced the o-rings?,they can affect oil pressure,
#5 here:http://www.realoem.com/bmw/enUS/show...diagId=11_2201

[Muzz258]

If you are getting the "red" oil pressure light blinking then you may have the following:

There is an oil squirter that spray oil up into the bottom of the cylinder, 6 in total (number 11 in graphic). It has a spring and ball valve to ensure that oil is only squirted when the pressure is above a certain level. The spring and ball valves sometimes fail, allowing oil to be always squirted and reduce the oil pressure in other part of the engine.

http://www.realoem.com/bmw/enUS/show...diagId=11_2167

[BimmerBreaker]

You said "high mileage" but didn't quantify it. As the mileage accumulates, the engine bearings get, er, "well broken in" and there is greater clearance between the surfaces and makes oil pressure more difficult to keep up, especially at idle when the pump is turning more slowly. I'm guessing that this only happens when the engine is fully warmed up and the oil has thinned. The light is just showing momentary drops in oil pressure. If it is just at idle, I wouldn't worry too much about it. If the vehicle is otherwise running OK, the cheap solution is to use a thicker viscosity oil.

If you are getting the "red" oil pressure light blinking then you may have the following:

There is an oil squirter that spray oil up into the bottom of the cylinder, 6 in total (number 11 in graphic). It has a spring and ball valve to ensure that oil is only squirted when the pressure is above a certain level. The spring and ball valves sometimes fail, allowing oil to be always squirted and reduce the oil pressure in other part of the engine.

http://www.realoem.com/bmw/enUS/show...diagId=11_2167

The oil squirters could be at fault if its a major problem, but at higher mileage it is somewhat common to see flickering oil pressure lights from time to time especially when idling.