Hi,
Vehicle: 2011 E200 CGI

Last week the station attendant filled my tank with E20, normally I always use 95 benzene.

Since then the engine light has been showing n the dash, error code P0234 and the car is always going into limp mode.

I have since been topping the tank up with 95 benzene, but this only corrects it for a short time, then it goes back to chugging then goes into limp mode.

Is this error code due to the wrong fuel going into the system or is it something completely different?

The nearest Mercedes garage is 2 hours drive, hence my search for an answer online first.

 

Interesting that nobody here has any advice to offer, anyway here is an update....

I drained the tank and refilled it with 95 benzene (unleaded), the car was fine with a some very minor judders. After 400klms the following problems happened:

- engine light came back on
- ESP inoperative
- Car went into limp mode

I scanned the car and the following fault codes are now showing:

- P2123
- P0234
- P2138
- B2aaa

I have reset them and tried again but the same happens.



Does anyone have any ideas? I will send it to the garage next week.

 

I have found this site useful in deciphering the codes.

https://www.autocodes.com/make/mercedes-benz/7

Just my $.02 worth.