[Vlad!]

Hi everyone,
I'm new in the forum and to owning a Mercedes overall
I bought my 2005 C230 Kompressor Sport Sedan a week ago and I noticed something wrong. If I push it too hard at higher speeds (~70mph) it will start to shake and sputter. This will go on even if i pull over and put it in neutral. If I turn it off and on again, the problem will go away, untill I push it hard again that is.
Any ideas?
I'm going to try to reset the ECU today using the gas pedal trick to see if it works..

 

[thancock]

Same Issue

I have the same issue...did you ever find out what was going on?

 

[Clutchholt]

It has a 2005 Mercedes C230 Kompressor Sport 6MT. One late night he and I were playing around from light to light, me in the wifes S2000 and him the Merc. On his second run he revved it out to its limiter and the car started to sputter really bad afterward. He pulled over and turned the car off, started it back up and he got a CEL. The sputter was gone but the CEL wouldnt go away.

 

[Lakeshow24]

Sounds like an overboost condition. The ECU will trigger fuel cut which causes the CEL and studdering.

Perhaps have a turbo vacuum leak. Check the turbo plumbing. If you hate the Mercedes dealer, check with a turbo specialist.

 

[thancock]

Took it to a Merc repair shop...CEL indicated coolant thermostat, ECU was shutting off a cylinder when the defective thermostat was sending incorrect high temp readings. $60 fix....

 

[QuoteWarz Insurance]

Luckily it was a quick and easy for fix for you. Nice to have those local shops that can get things fixed without having to take it to the dealer and pay big bucks for repairs and diagnostics.

 

[Lakeshow24]

Of course I would have a brain error and forget to tell you to always check the codes first. Start with easy and work your way down to the complicated stuff.

Check engine codes are always the way to go first. When fuel cut hits due to overboost the engine will also throw codes that tend to go away when overboost conditions are eliminated.

 

[Vlad!]

Thanks for your replies, i hope it's gonna be an easy fix.. I still haven't found out what the problem is yet, but i'm going to take it to the dealer on Monday for a full check-up.. wish me luck..

 

[QuoteWarz Insurance]

Sounds good. Let us know what the dealer says. Hopefully they won't charge you too much to figure it out.

 

[Vlad!]

Just as an update on this, the dealership first diagnosed this as a case of oil leak from the camshaft adjusters which had gotten to the Oxygen sensors and messed them up, so these had to be replaced (they cost me around $400 a piece, they had to get them shipped from Germany). Bad news is after replacing them they are still getting a code which basically meant the valve springs and fuel injectors need to be replaced. They quoted me $2200 parts + labor, AND they said that the ECU might be malfunctionning too. Needless to say i told them to leave the car as is, I'm going to look elsewhere to repair it, this just feels like throwing money into a bottomless pit!