My mom's 2000 E320 has developed a horrible engine resonance and vibration. It happens when the car is in gear idling, and the engine is cold(in the morning). The resonance from the engine is very loud(booming in your ears), and the vibration is way too much to be normal. It goes away after the engine warms up a little(about 5 minutes of driving). There is definitely something wrong, because even when the engine is at normal temperature, there's still a vibration through the interior at idle, and when taking off from a stop....could it be loose engine mounts or something more serious??thanks
PS- the FSS indicates 2000 miles until next service, should it be taken in before? Also, whether this has any significance at all, the car has almost 52,000 miles, and only Shell V-Power is used, which has tons of detergents and cleaners which I hear isn't too good for Mercedes engines...

 

Possible catalytic converter issue. I do not like V power since it only has 91 octain. I like 92 octain premium unleaded at AMOCO

 

thanks E320star. Anybody else have any comments on this problem?ever experienced it in your car before?

 

check the motor mounts and/or anything inside the engine that could be bouncing around (aka lose parts)

 

Put it up and look underside, sounds to me like something is rubbing, exhaust pipe, broke motor mountm broken trans mount, Engines don't vibrate internally and run for very long. They get worse quickly.

 

Since you say that the sound goes away after the engine warms up, so I too would think it may be exhaust related.

As far as extra octane, since the cars are able to run on 91 octane, anything higher really does no good, because the extended burn time is not used regardless. Here in the east we have 93 octane (PA).

 

just an update for those who have helped me---> Messerchmidt and oldwheels, you were right, both of the motor mounts were collapsed. Our service advisor covered it under warranty, even though the car is almost 5 years old. Also, service A was done(FSS indicator), and they charged $190(!!) for just an oil change and oil filter!!The service advisor said that we should buy an extended warranty if we're going to keep the car for longer, but is that necessary??

PS-the Enterprise woman told us that they bought 40 brand new 2005 C240's earlier this year for the dealership here in Fresno. Say they bought the car's at MSRP(around 33,000), that's $1,320,000!! I realize they had to have got a discount for fleet sales, plus the money for rental fees, that's still tons of money though. They charged around $40 dollars for 24 hrs, it was desert silver '05 C240, much improved over the '01 to '04.

 

Yes, get the extended warranty if you want to keep the car.
Unexpected repairs can add up quickly.

 

If you read again what you wrote above (post edited by moi) you should already be on your way to the mechanic by now. My mom always told me that a big problem always starts with a small problem. Therefore while your problem is still small (and if you love your mom), just please bring her car in for a check-up....

 

and if you read more of the posts on this thread, you'd see that we already did