Sorry to repost, but I think I put this in the wrong forum the first time. I'm a long time reader, new to posting though.

I have a 2006 C230 sport, V6 (obviously ).

I just changed spark plugs and replaced both filters with K&N air filters. I had no issues the first day but now the Check Engine light is on. I had Autozone run the codes and it said it's running "Lean."

Can the filters do that? Is it going to self adjust (i.e., like altitude changes)?
Is there a manual adjustment I need to make?

The car runs fine, and I'd hate to have wasted $120 on filters only to have to revert back to the paper ones.

 

are you sure you didnt leave a vacuum hose off, or pulled one by accident. i see benzes with K&N all the time.

 

OK, I checked and didn't find any vacuum leaks. I also checked to make sure that the gasket that gasket that goes around the Mass Air Flow sensor was OK and it was. The Airbox is sitting fine. I'm still getting the check engine lights. Anyone else have any ideas?

I've seen several MB's with K&N air filters without issues. I also have run K&N in ALL my previous vehicle without issues. They're better for the environment and a cleaning every now and then is all they need so the maintenance is nominal.

 

I'm beginning to get the feeling these models are very "finicky" when it comes to check engine and asr/bas and window functionality and headlight timers and lighting system warning lamps etc etc ad nauseum.

Sadly they seem a bit too precisely engineered for real world long-term use. I encountered similar non-electronic issues with a prior W116... the "always something" syndrome.

 

I have a 98 C230 and run the stock paper filter, I have not bothered changing it to a K&N because the stock filter is very large and has plenty of flow for the naturally asperated engine. I do have K&N filters on several other vehicles I have, and many of them have over 300,000 miles on them with no engine related problems. The most noticable improvement I had was with a 99 Ford super duty with Power Stroke turbocharged engine, it increased my fuel economy by 2 MPG! When I got rid of it at 300,000 miles, the engine was still running strong, but the transmission wasn't. Improper cleaning is the majority of the filter failures, using compessed air to dry, using high water pressure to clean, all of which tears holes in the filter media.

 

Exactly, thats why I have not bothered changing to a high performance filter on my C230, the naturally asperated 4 cylinder does not suck as much air as a turbo or supercharged engine, so very little would be gained from the K&N or the one your suggesting for this motor.