Oil Level Sensor Warning?

[jehu]

I have seen this a few times recently.. The dipstick level is fine. I had a level sensor fail once and the way I discovered it had failed was the Engine Oil Low Warning came on and never went out even when the level was right.

Is this possibly a connector fault or it this an early alter to a failing level sensor?

[shogun]

Usual fault is a bad/dirty connector , check this plug under the engine https://www.ecstuning.com/b-genuine-...r/12611704468/
On my E32 these 2 wires go up to the area next to the B+ post, and there is another plug connection which could fail http://bmwe32.masscom.net/sean750/sp...gConnector.jpg
if that is all o.k., then the sensor could be dirty inside and stuck, someone on the German forum took it apart and cleaned it for his M70.

[jehu]

Thanks again... I replaced one on another e34 and when removing it realized the plunger or whatever its called which moves to give the readings may simply have become stuck and a good cleaning might have repaired that but since I had the new part in hand I just installed it... never saw this message till driving this 540.

Usual fault is a bad/dirty connector , check this plug under the engine https://www.ecstuning.com/b-genuine-...r/12611704468/
On my E32 these 2 wires go up to the area next to the B+ post, and there is another plug connection which could fail http://bmwe32.masscom.net/sean750/sp...gConnector.jpg
if that is all o.k., then the sensor could be dirty inside and stuck, someone on the German forum took it apart and cleaned it for his M70.

[shogun]

translated from the German forum: Oil level switch in E31/ E32 / E34 , The oil level switch essentially consists of 1. The sensor in the bottom of the housing, 2. The float in the housing, 3. The lower part, 4. The top
The bottom of the float is magnetic. If this side comes too close to the sensor, this signals "Check oil level". The oil level switch is installed from below in the oil pan and is "almost" completely in the engine oil. This can penetrate the float chamber through two openings in the housing and lifts the float. Over the years, deposits form on the bottom of the chamber, which on the one hand adhere to the float and thus give it more weight, and on the other hand can "stick" the float to the bottom if there is too little oil. If you want to try to repair it, you can choose between 2 variants. Chemical. Dip the oil level switch in so that the oil and oil deposits (mud) dissolve so far that the stuff can run out of the small openings. Must be repeated several times. The float should click audibly when the housing is tilted and leave the impression of a freely moving component. Mechanical and chemical , First of all: The upper part of the housing cannot be turned! It is fixed with 2 grooves on the inside! The housing is opened. To do this, the cover must be removed from the top. The lid is a thin aluminum sheet that is fixed with a very small protruding and bent edge of the upper part of the housing. The perfectionist bends this bent edge up with the finest tools and simply removes the lid. The rustic handyman pries out the lid and destroys it. Under the lid in the center is a kind of solder point. This is the end of the rod on which the float moves up and down inside the case. The soldering point must be melted and ideally vacuumed off the solder. While the solder is liquid and the rest of the case is really very hot, the (hot!) Upper part has to be pulled up from the lower part. t After separating the housing halves, you have free access to the float and the float chamber. Mark the bottom of the float. It is magnetic and allows the sensor on the underside of the oil level switch to respond. Now clean everything and reassemble and hope that the sensor is not broken. Because then all work was challenging but unfortunately purposeless.

[ross1]

"The rustic handyman"


Thinking of changing my user name

[jehu]

What would be the best chemical to dip for cleaning? Naphtha?

translated from the German forum: Oil level switch in E31/ E32 / E34 , The oil level switch essentially consists of 1. The sensor in the bottom of the housing, 2. The float in the housing, 3. The lower part, 4. The top
The bottom of the float is magnetic. If this side comes too close to the sensor, this signals "Check oil level". The oil level switch is installed from below in the oil pan and is "almost" completely in the engine oil. This can penetrate the float chamber through two openings in the housing and lifts the float. Over the years, deposits form on the bottom of the chamber, which on the one hand adhere to the float and thus give it more weight, and on the other hand can "stick" the float to the bottom if there is too little oil. If you want to try to repair it, you can choose between 2 variants. Chemical. Dip the oil level switch in so that the oil and oil deposits (mud) dissolve so far that the stuff can run out of the small openings. Must be repeated several times. The float should click audibly when the housing is tilted and leave the impression of a freely moving component. Mechanical and chemical , First of all: The upper part of the housing cannot be turned! It is fixed with 2 grooves on the inside! The housing is opened. To do this, the cover must be removed from the top. The lid is a thin aluminum sheet that is fixed with a very small protruding and bent edge of the upper part of the housing. The perfectionist bends this bent edge up with the finest tools and simply removes the lid. The rustic handyman pries out the lid and destroys it. Under the lid in the center is a kind of solder point. This is the end of the rod on which the float moves up and down inside the case. The soldering point must be melted and ideally vacuumed off the solder. While the solder is liquid and the rest of the case is really very hot, the (hot!) Upper part has to be pulled up from the lower part. t After separating the housing halves, you have free access to the float and the float chamber. Mark the bottom of the float. It is magnetic and allows the sensor on the underside of the oil level switch to respond. Now clean everything and reassemble and hope that the sensor is not broken. Because then all work was challenging but unfortunately purposeless.

[shogun]

try brake cleaner, use the straw of the can to fill the sensor thru one of the 2 holes, then shake the sensor that the sensor float moves, drain dirty fluid, do the same procedure again till the float inside moves easy and clicks.