contact148

2003 c240 4matic wagon 123km on car was 3C out today and misty rain if that matters

changed the oil approx 5k km ago

tonight on the way home from work dash went red and I got the reduce engine oil level

nobody has touched my engine
dyno mode engine off oil level is 8.5 liters


so i left it for 15 mins went out malfunction was gone but approx 5 mins into my drive it came back reduce oil level

so WTF any ideas Im pretty sure its not overfilled

just took the oil filler cap off and its full of that yellow goo from condensation since i do 99% short trips maybe i need to run it on the hwy for a bit to burn off anything in the oil??

Glyn M Ruck

It's either:

- Over filled with oil
- The level sensor is Kaput
- You have a dribbling injector or have picked up a tank of gas contaminated with diesel. The fuel has not ignited & run down past the rings & diluted the sump oil causing the level to rise.

You should have an oil sample analysed for fuel dilution. More common than you might think. If there is no fuel in the oil then the other alternatives apply as long as there is not coolant in the oil.

contact148

oil level on dyno mode is 8.5L oil has not been added in months

is 8.5L the correct amount for my engine??

would short trips cause too much moisture to build up in the oil?

I do get alot of yellowish gunk on the oil filler cap in the winter...not in the summer through

head gaskets are not a known problem with this engine are they?? (03 c240 4matic wagon)

C230Krarana

If you have a dip stick for engine oil check it at the gas station (where it is suppose to be level.) if oil is at the mark or between mark then senor in pan is in question. changing the sensor mean draining the pan. the goo is moisture built up but also might a small amount of coolant? I hope not. running on the high way does not burn contaminates. once in oil stays in oil and an oil change is needed with filter. not saying you need oil change now. but manually checking with dip stick is a sure way to see if sensor is lying.

Hope this helps.

Rom

PS happy thanks giving if in US.

contact148

nope no dipstick for this car

I read before the goo is normal on this engine as the filler neck for the oil is plastic and condensation forms there

Glyn M Ruck

Repeated short trips in cold weather can get free water level in the sump up as high as 7%.
I've proved this on a Dyno doing repeated testing back to back for months over 20Km from a cold start without a long hot run when testing friction modified engine oils.

These engines do not usually blow head gaskets.

If you go back to my very early posts on this forum I tried to establish the exact oil capacity for the M112 2.6 litre engine with filter. It's all over the place & no one knows. Even my owners manual is contradictory. It suggests about 8.6 litres but my car has never taken more than about 7.8 to full.

Glyn M Ruck

If you have any worries then send a representative oil sample to Blackstone.

contact148

at the blackstone site now

so IF i have excess water in the oil will a long hyw drive burn it off???

Glyn M Ruck

Yes!

The best thing about an oil sample is that it will tell you immediately if it's water, or coolant or fuel in the oil - or if you have nothing to worry about & need to drop the level slightly. Explain when you submit the sample that you are worried about these three in the oil & expect them to report findings properly. Blackstone is an excellent lab but don't leave them guessing.

contact148

im going to extract approx .5 liters today If i take a little too much its easy to addd more

Glyn M Ruck

If you are going to use part of that as a sample then run the car for a few minutes before extracting oil to ensure that the sample is representative. Then give it a good shake before transferring into the sample bottle.

Xhale707

If your car is reading 8.5 in dyno mode your car has been over filled.. It should not read 8.5 or more around 7.2-7.7 MAX. The reason for this when you floor the car the oil will raise higher than 8.5. You could even check for your self. Put the car in dyno mode go drive around for a mile or so watch the qts jump up and down when you play with the pedal. 100% you over filled your oil. Reduce engine oil has nothing to do with bad gas... lol Bad gas would give you misfires not a REDUCE engine oil malfunction.

When changing the oil in your car. If you don't have a pump to messure how much you took out.. Start with 5.5 qts and use the on board computer. It will tell you how much to add. Ive changed my oil 9 times so far owning this car. 1 time was due to me being stupid and wanted to use the wrong oil.

I have two C class that i work.

I would at least take out 300ml 2 be safe

Glyn M Ruck

Raised oil levels frequently have to do with bad gas & it does not cause misfires. I will put 20% diesel in petrol & your vehicle will appear to run fine but the sump level will steadily rise.

Xhale707

But why would you wanna put diesel in my gas =*( after all this time and help nooo

Glyn M Ruck

Because mistakes happen in bulk fuel terminals when filling delivery trucks.

contact148

the 8.5 liters was with engine off

I filled this car back in july/aug and have put allmost 6K on it and only yesterday did the warning come on..... which i find strange that it took 6k to figure out it was overfilled

I removed 400ml today

I put it on dyno mode and extracted a bit at a time untill the oil level check said it was oil level ok

Glyn M Ruck

Yes - It does not make a lot of sense - unless it's one of the items above. Keep an eye on it.

JLD2k3

I get the "Reduce Engine Oil" message after about 30 minutes of driving every time the dealer changes my oil. After a couple of weeks it goes away.

contact148

well it took till a few days before christmass to get the kit i had the oil i removed from engine (from the start of this thread) in a jar I sent it to blackstone labs and here we are

Oil Analysis

as you can see i have a high amount of fuel in the oil

so why?

I do 99% short trips with engine hardly warming up (its 10mins to work city staying under 60km/h both ways)

about 2 weeks ago i went for a 2hour hwy drive and put in techron before i filled up I use shell 91 gas allways so do I have a leaking injector? my mileage sucks

or is it all the short trips causeing this???

Ive put about 2500km on it since I corrected the oil level and its been fine since should I do an oil change soon? (7500km on mobile 1 0w 40 oil and fleece filter)

Alan B

How much does Blackstone charge for this service? What is the turn-around time?

contact148

25.00 and a few weeks depending whre you live Im in canada and it was christmas mail rush so it took a while to get the kit to me but they got my sample regular mail in about 2 weeks

mleskovar

Glad you got this sorted out. As an addendum......8.5 quarts in the engine can show about 7.5 quarts dyno mode. A quart or so can remain in the filter/housing. That's why you want to loosen the filter cap to let air in when draining oil. The first time I changed my oil I drained it until it completely stopped dripping.....took a while. Then I added 8.5 quarts and the dyno mode showed 7.5. It varies for me from 7.5 to 7.7 after changes. I also did some tests to see how long it took for oil to drain from galley ways etc. to see if that affected anything. It does....up to 1/2 quart over an hour's time from when it starts a slow drip.

Glyn M Ruck

This report is a little strange. You are getting the car hot enough for long enough to drive off all the water from cold starts but you have a very high fuel dilution that you are not managing to evaporate off. My C240 is also a short trip car and builds a little water in it's samples but zero fuel - My car has done 61,000 Km. You must not allow this to continue - your wear levels are excellent but fuel dilution of the lubricant - if it's allowed to get too high will show first in bearing wear - yours is fine so don't panic - lead, tin & copper are under control.

My conclusion is that this level for fuel dilution is too high to be purely from cold running.

Likely causes:

1) Temp sender unit is faulty & is misleading the ECU & causing the vehicle to run too rich for too long when cold because the ECU thinks the engine is colder than it is.

2) You have a dribbling injector/injectors. Your mileage is low for injector problems but they happen.

You can intersperse your short trips with a long hot run & do another sample to see if this improves matters or you can tackle the items above. Your car might also benefit from a cold temperature thermostat rather than the standard 87 deg C one.

Good luck!

LILBENZ230

I was only able to get a 90 deg C thermostat for replacement of my stuck OEM one on my 05 230K. This should be fine, no?

Glyn M Ruck

Yes.