PJPublow

I currently bought a 1999 E320 wagon 230000kil and the previous owner was using synthetic oil which I recently changed back to regular oil. I just checked the oil and inside it looked like light colored brown milk. First time I have ever seen this in any car that I have owned. The car is also running real rough at over 80 kl per hour. Any ideas what could be wrong? Blown head gasket? How much to fix? Any other ideas? HELP!!!!!

CA_Tallguy

Welcome to the forum - please use more descriptive titles when posting a thread rather than just your model.

It sounds like you're freaking out though... so the first thing I'd suggest is to calm down and work through the issues logically.

When did you buy the car? Has it been rough since you bought it, with both the old synthetic oil and the new regular oil? Or did it get rough when you changed it?

So the car is only running rough at higher speeds, correct? Is it rough all the time at those speeds, or does it get rough (or more rough) when you are accelerating? Do you notice if the roughness kicks in right after the transmission shifts into a certain gear?

One of the more common causes of vibrations is bad engine mounts. Your problem could be as simple as that. It is hard to say without more information from you about the problem.

ohlord

engine needs 0w40 synthetic and fleece filter.
You are being foolish changing to conventional which has caused failure issues in the past.
Peanut butter colored sludge is a combination of condensation and oil.
Flush the engine with a quart of kerosene in the oil idled for 15 minutes. Extract the old oil,install fleece filter install the proper oil 0w40 syn
it will last 10k miles on the fss system and keep you and your engine happy.
Where are you located?
Have you changed your spark plugs single electrode platinum bosch 7422
ngk 7090.
Have you scanned the car for pending obd2 codes?
Have you installed a fresh air filter?
Have you cleaned your mass air sensor with proper mass air cleaner (crc brand)

This engine was designed to use synthetic oil.
Why would you change?

PJPublow

Should I change back to synthetic? Tallguy, it just seems to start shuddering at 80. I bought in Oct/2011 and it ran perfect. I have only put 6000 kil on it.
Ohlord, thanks for the suggestions, since this just started on Thursday, I have not tried anything. I was going to take to mechanic on Monday and wanted an idea on what could be wrong.

CA_Tallguy

I'm still not clear -- when did you switch the oil? Did the vibration start at the same time? If so, then it is pretty clear that the oil service is likely the cause. If not, then you may have more troubleshooting to do. If you are not going to work on the car yourself (there are many jobs where instructions are posted on this and other forum sites), make SURE you take it to a qualified mechanic (find a highly recommended independent)!! DO NOT take it to whatever place put that oil in it!

Yes, you should switch back to synthetic as OhLord says. Follow the list that OhLord posted and read up on the forum here about other common issues and 100,000+ mile service items (changing motor mounts should be one of the first things if not done yet) and your car should give you years of pleasure.

PJPublow

The oil and the shuddering do not coincide. Oil was changed about 3000 kil ago. Shuddering just started Thursday. I will talk to the mechanic about what Ohlord mentioned. Thanks for your thoughts. I thought it might have been a blown head gasket.

Hirnbeiss

What is your normal running temp, and how long is your typical drive? If it isn't breaking 80C, I recommend changing the thermostat - they tend to die off with age for some reason (at least mine did). The condensation occurs when the engine doesn't warm up enough on its daily runs.

CA_Tallguy

It sounds like you changed the oil perhaps a month ago, maybe a little more? That isn't a whole lot of time. As OhLord mentioned, sometimes changing the oil from synthetic back to regular can cause issues. So you can't rule the oil change out as something may have taken some time to go out after it was done. Of course, if the problems had started immediately you could pretty much count on that being the case but the odds are a little less since some time has passed.

Since the oil change was very recent, I'd still think chances are greater (vs. some other random problem having occurred) that the oil change led to an issue.

Does the vibration kick in anywhere in a certain RPM range when you put the car in neutral and rev the engine? Just wondering if there is any way to replicate the issue under a condition other than transmission is engaged and you are moving. Also, does the probem happen while moving if you let your foot off the accelerator? I'm not sure if it is entirely wise to try this, but maybe put your car in neutral and coast at that problem speed to see if the vibration remains. Doing various tests like this might help you narrow the problem down towards the engine, transmission or suspension/steering/chassis.

Heck, what you are describing could even be a bent rim or wheel balance being off based on what you've told us.

Please keep us updated with info from your mechanic as you work this out!

PJPublow

Tallguy,thanks for getting back to me. The shuddering has stopped and the car seems to be back running as normal. It could have been iced jammed up underneath my car as my son had it out last Thursday in a pretty bad snowstorm. We are experiencing milder temperatures now and the snow is melting. The car seems to be OK. Maybe I was just freaking out and thinking the worst.