Coolant in oil?
1999 E320 with 144,000 miles.

Began needing coolant 5 weeks ago.
-experienced 2 Low Coolant messages since/used whole container of standard 50/50 coolant in past month.
-no visible leaks around engine or on parking surfaces.

2,000 miles since last oil change 5 months ago at drive through shop that claimed to use Mobil synthetic (8 quarts.)
-5 days ago the oil looked sort of worn/old.
-2 days ago I got Max Oil message twice while tooling around town. First message came after car started accompanied by a ticking sound that quit after being turned off and restarted.
-Brought the car to the oil change place thinking that warmer weather expanded the 8 quarts of oil.
-Service personnel said that coolant had leaked into oil, probably from bad head gasket. they showed me milkshake looking sludge in oil cap / oil on dipstick was milky and slightly rusty looking.

Brought the car straight to family's regular foreign car mechanic (who is retiring).
Today after picking the car back up from the shop because the new staff said that they wouldn't "do a job that big", I checked the dip stick and it looked like there wasn't any oil on the dip stick and the rusty color of the oil residue was gone, but the oil cap and throat were full of that milkshake sludge.
-the Max Oil message did not come on during the way back.
-coolant level has remained the same for past two days (maybe 20 miles).

The car still performs like it just came off of the showroom floor, and isn't overheating (constant 80c once warmed up). No smoke, ..nuthin; coolant is normal green tint as always- never had oil in it.

Anybody know what's causing the car's malfunction?

 

Is this what your oil cap 'milkshake' looks like? https://mbworld.org/forums/e-class-w...my-engine.html

I might suggest getting an oil change from a more reputable shop. Did the mechanic give any explanation?

 

Thanks for the reply-
yes, that's what it looks like. - pale yellow pudding.

just checked the dipstick in daylight- it's full and still thick and dirty looking but not as bad as when the oil change place first showed it to me.

The mechanic shop said cylinder head gaskets were bad, and gave me an estimate on the work that they said they wouldn't do: L & Rt cylinder hd gaskets, Intake Manifold gaskets, Timing O-ring-s, V/C gaskets, Cyl. hd bolts, Timing chain gasket, Oilfilterkit, Synthetic oil, Antifreeze = $383 parts, plus $2,633. for 25 hrs. labor, plus $900. for sublet (electronics),
-for a grand total of $4205.00. before they could tell if they needed to shave anything.
Thought it wise to get a second opinion.

 

i'd look around in junk yards for a new power plant before I rebuilt one for that kind of coin.

 

read the link I posted. If your coolant levels normalize and you dont have smoke or sweet smelling exhaust your engine may be fine. The milkshake is generally a sign the car was driven short distances in the cold and not allowed to reach normal operating temps.

 

That sludge in the cap is normal in most cases.
You have the wrong type anti freeze in the engine if you are Green.
Neither mb fluid nor the same speck fluid ,different dye color zerex GO5 are Green.
Change it,have a coolant system pressure check performed to locate the leak (most likely a hose) Get or have a combustion gas test kit and perform the test for combustion gasses in the coolant.
Start changing your own oil.
http://www.peachparts.com/Wikka/OilFilter2
easy enough,no crawling under the car and you know it was done correctly and filled correctly and filled with the correct oil correctly
Get some sleep

Oh yea,
Run from that shop,as far and as fast as you can.

 

All of the above, plus replace the thermostat for good measure. It should give you a few degrees of operating temperature (right above the 80C, 87 is the design temp), which was all I needed to keep crankcase condensation at bay in the winter (in Delaware). The old ones tend to "tire out", or start bypassing too early.