Thanks for the info John! I really appreciate it.
The reason I ask this is because I have a slight rattle from the engine bay when the car is idling, and only when idling. I can't find the exact location of it. I have checked everything for looseness, replace a few clips (for radiator and 2-fan shroud). Didn't solve problem... and I *think* that it's louder when the oil cap is off. Would that make sense? Thanks again!

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2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

THanks for the help John, I really appreciate it. I will definitely keep an "ear" out for it. Thanks again.

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Thank you for your advice and your insight.

I am the second owner of my car. The previous owner was on old man who let the car sit for two months before even trying to sell it. One time it shows in the maintainance log that it went without an oil change for almost 16 000 kms!!!

I'm using Castrol GTX 10W40 that has always been the brand of choice at my dealer (the same dealer the car was originaly sold at)

I've now owned the car for 10 months and have been more than pleased. I'm tickled with it!!!!

I've bled the brakes, flushed the coolant, transmission fluid and have been changing the oil in the 4-5000km interval.

This car idles silently know with the new serpentine belt.

Any other areas you recommend Larry? What about rear end links or bushings? (car is all original with the exception of the tires, serpentine belt and brakes) I also dissembled the intake plenum and throttle body and cleaned it out since it was covered in oil sludge and carbon. PCV hose/breather element was clean and no oil or sludge in the air cleaner element tray so that was a relief!!! I doubt the motor has any sludge buildup in the bottom end, top end looks and smells fresh (aaaahhh)

Thank you again for your knowledge Larry!

Respect,

Mike McKinney

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1989 300CE - 269,000 km
1994 SL600 - 59,000 km

SHYNE,

Sounds like you're doing all the right things. Just keep changing the oil and pay attention to noises, watch for leaks and fix the little problems before they turn into big problems.

Good luck,