I have a 2006 C230, which I love! Truly. However, I'm getting an average of 13 mpg!

 

Yes, my CLK 230's average fuel consumption has dropped considerably recently. Other posts suggest it could be the Mass Air Flow sensor. My check engine light is also on and my earlier post points to oil in the ecu unit. Would be very interested in any suggestions. Joe.

 

How about fuel quality? If you have a lot of alcohol in the mix, your mileage drops. When I had to fill up with ARCO [sm=bangbang.gif] I went from 24-27mpg avg to 19 mpg in one tank which corrected itself with Chevron fuel. The ARCO here in Washington state(as I understamd It) is the California blend to save distribution costs.

What brand do you use? A rich mixture or defective MAP should bring up codes and your idiot light.

For a test you could reset the master computer. To reset the computer you could disconnect the battery for about an hour and your fuel mixture will reset. Get your radio code out first or NO RADIO...

Also, check your air filters, sometimes they get dirty in short order do to local conditions and they can destroy mileage. Hope this helps.

 

still under warranty? what s the mileage check air filter. go with chevron premium.or shell