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2001 Mercedes E-340 4-Matic loses acceleration suddenly and unpredictably + vibration at stop

We have a 2001 E320 4-Matic. Recently, it has developed a serious problem. Every now and then, when I come to a stop (e.g., at a red light), the car would shake/vibrate significantly. Even more importantly, the car seems to lose acceleration suddenly and unpredictably (not necessarily correlated with vibration at the stop). The latter problem goes away “for the moment” by switching off the engine and then restarting it. The Check Engine light has come on as well. The codes that are diagnosed are P2001, P2003, P200F, P2082, P2050, P20151, P2055, and P2053.

While there are several issues with the car, I am most concerned now with the two issues I highlighted above - sudden loss of acceleration and the vibration while stopped (both happening unpredictably). I took the car to two mechanics. The two mechanics seem to sharply differ on how to resolve the “sudden and unpredictable loss of acceleration” issue. One mechanic (Mercedes dealer) attributes the problem to issues with EGR valve and claims replacing that will fix the problem. The other mechanic attributes the problem to the Catalytic Converter which he says is broken and is causing sudden loss of acceleration (and yes, there was a rattle some time ago). The second mechanic does not disagree that the EGR valve (and the secondary air injection system) has issues but he says it is the Catalytic Converter which is causing the core problem of sudden loss of acceleration (and yes, there was a rattle some time ago).

Each of these are expensive repairs but what is worse is that the two mechanics don’t agree on the root cause. I would really appreciate any advice/thoughts from all of you. Thanks in advance

Please tell us the current mileage and a complete list of maintenance and repairs the car has had over the years. After that we can better judge what your best options would be.

You also need more competent mechanics rather than guessers.

A Mercedes is an expensive car to maintain, and on average owners spend about $1500 per year or more to keep them running .

If you have not done that then all the problems are cumulative and a result of neglect.

Mileage is just above 125,000 miles and definitely under 130,000 miles (I think that it is something like 125,400 or so). Sorry. All recommended and scheduled servicing has been done so far.