WHAT? My oil light is on? WHY
 

As I’m driving to work this morning my OIL LIGHT comes on, it takes my brain a full 2 seconds to freak out and turn the car off and drop it into neutral. I was going UP a hill and then coasted down the hill, down the exit ramp, and down the feeder and next to a shell station. At least god takes care of me sometimes. I really shouldn’t complain. So I get out pop the hood and check the oil it’s at the ½ mark. Just like I always put it not too high, not to low just right, so I check it again. SAME. Damn, I must be going crazy, and I’m to young to go crazy.

So I start the car back up again, and all the lights go off but the oil light, then after about 4 seconds it goes off. I let the car idle and pull it slowly into the parking lot. (Yes, I was still on the feeder, with cars racing by like they are in NASCAR. I let it idle for about 3 minutes and then turn it off, and back on again. NO LIGHT.

So then off I drive the rest of the 10 miles at about 30mph (traffic) to work without a problem. I changed the oil about 2 months ago with AMSOIL, and a standard MANN filter. At the end of the month, I’ll be dropping in another MANN FILTER like I always do and I’ve been using Amsoil for years. I’m freaking out. I mean I can drive my truck around, but please it’s not a MB.

I changed out the timing chain about 9 months ago. Could my oil pump be going out, could it be a bad fuse? I did change over my fuses to the correct MB cooper fuses about a week ago. But that can’t be it. I haven’t had any issues at all with fuses. Going crazy and scared to drive my car any help would be great.

Thanks Michael

Any knocking from the engine?

Does your car have a working oil pressure guage?

Could be a bad pressure sender as well.

If its the SDL the light is a low oil level indicator not low pressure. Check your oil level. My SDL oil light will come on once in a blue moon just to give me a wake up call (heart attack). But I have never found an issue with oil level or pressure. Just an old car hick-up

I think those level lights are flakey. also, you were going uphill, perhaps the oil was off the sensor long enough to trip the light.

The oil level at 1/2 and transversing hills. Sounds like the sensor worked as advertised.

Don't worry about it.

The oil level float switch does fail occasionally. I've replaced a couple of them. They are about $40 and you have to drain the oil pan so do the job during an oil change. The float switch is on the left side of the oil pan and is secured by two screws. Make sure you replace the o-ring seal also.

Agreed, the change in inclines probably caused the light to turn on momentarily.

This happens to my 190E as well.

It is an interesting wake up call when it happens.

Okay, that keeps my mind in check. So I need to change out the float switch that is located on the left side of the engine and has two bolts holding it on. I can totally do that.

My pressure gauge was and is working just fine and the engine wasn't making any noise at all.

I'm so glad that it's just a sensor that I need to replace. Off I go to find out how has this sensor switch.

You are the man. Thanks for the help everyone, I've found the part I need. I'll check to see if Phil has it, makes me feel dirty if I have to order from anyone else. :rolleyes:

Here is what it looks like for the next person that has this issue.

http://www.autopartsworld.com/results/?PN=4294895916&N=0&VN=4294967241+4294966748+4294965203+4294967247+4294967124&Nr=AND(universal:0)

And Gasket
http://www.autopartsworld.com/results/?PN=4294895914&N=0&VN=4294967241+4294966748+4294965203+4294967247+4294967124&Nr=AND(universal:0)

Thanks again.

On my TD, when the oil level is 1/2 way between the high & low, if I brake hard or turn sharp to the left, the light comes on for a few seconds. When the level is close to the minimum mark it comes on more often. When it is at the full mark it never comes on. Makes me wonder about the rational about running the level 1/2 way between the 2 marks.

That's a good point. I was thinking about that last night, so I added more amsoil to just right under the full mark. But then I start to worry if I'm adding to much oil. God there is something wrong with me. LOL :D

But really the oil level sensor is working correctly. I drop to work today and went up and down some over passes and the light never came on.

Cheapest fix ever.

For a good while I've suspected that the half full argument is caused by a slow leak from the turbo drain tube where it hits the oil pan.

In my engine that I just installed in my SD, the oil was visible in the tube's attachment hole when the engine was sitting level in the garage, and at less than full on the dip stick.

I'm guessing that a seal in less than perfect shape, combined with a higher oil level would promote the leaking of oil, down to wherever it balanced out. The half-full mark, possibly?

I've been running my Mercedes engines at the full mark for almost 20years now, ... haven't had a consumption issue. Either it is pre-124, a myth, or something like Josh is postulating.

hey guys, it's a half low mark, not a half full mark. you are only down one quart at the 1/2 low mark... half full would put you down 4 quarts...

I just changed the oil in mt 81 and put in 6 plus qts to the full mark.
Also did the oil filter.
Who has an 8 quart sump?

X2 John,
You will see I was careful to say high & low marks!!

It is surprising that Roy has not chimed in as he has strong views on oil levels.

I do think though that running at the high mark on some motors could restrict the turbo drain, causing the turbo bearing cavity to flood & if the turbo has an oil seal issue, it could allow oil into the inlet & contribute to a run away.

How could you restrict the turbo drain if the oil level (not running) is several inches below the turbo?