stangxs

I searched and haven't found a clear answer. My car has 10K miles on it, service "b" was done at 8500 miles, I don't beat the car, and charcoals have been removed for a while now.

Should I not worry about the CEL, I read somewhere it takes the ECU times to adapt to the K&N, and after ~18 on/offs the CEL will go away? Is that BS? Or should I just take it to the dealer? Thanks.

Sincity

I only know of you and JonMB (forgot his complete SN) that has a CEL from K&Ns. Did you seat the box top snuggly? I know that to be a problem for some and the CEL cleared after they reseated the box tops. Also, check for leaks at the rubber connector to box top.

Even Money

This is easy to screw up. You think you have it on snug, and in fact, it isn't. The back of the box top by the Y connector is a tight fit. Once you think you have it, you have to peer underneath, maybe with a flashlight, to check the seal isn't being pinched in the back.

stangxs

hmm, just took the airbox apart and checked the filters, everything lined up perfect/snug, put it back on a started the car, CEL is still on, obviously.

So should I just drive it for a few weeks hoping the light will turn off?

C63newdude

This is no coincidence, this is an outgoing issue. I reported CEL with K&N a while back. Since I put the stock filters I never had any CEL ever. Look at what I posted a while back:

https://mbworld.org/forums/c63-amg-w...ult-codes.html

We also have a couple of things in common, poor gas and heat. Believe it or not this combo doesn't help either.

clktoc63

Actually, I find that very interesting. Wouldn't the lean condition imply that the K&N is offering a whole lot more airflow? Seems like that would be a very good thing if you could adjust the tune to throw in more fuel...no??

goatfarmer1970

Could be unrelated, but my pretty-performance-oriented service advisor said that a lot of people get CELs from low RPM city driving (carbon build-up?) and even went so far as to say that the techs joke that "a redline a day keeps the CEL away." No idea if there is any validity, but mention just in case someone more knowlegable can comment.

TTMotorsports

Reset the ECU since there is a larger volume of air getting into the intake manifold and it needs to reset the MAF calibration.

If you are sure that the filters were installed properly and the bottom of the y-pipe isn't dislodged by the firewall then you should be good to go.

TTMotorsports

Utter nonsense!

GBlansten

With the huge subjective performance gains that aftermarket air filters offer, I wouldn't worry about a check engine light. Just enjoy the sense that you have done something positive to your car.

stangxs

Thanks for the info, guys!

Probably a stupid question, but I'll ask anyways. Resetting the ECU is just dis-connecting the battery, am I correct? I have a eurotune, will this remove the tune?

Thanks.

C63newdude

Technically yes it changes the air flow to more air intake but also technically the ECU compensates or more fuel that is why the MAF is there.
I just don't have the tune for the car so there is no way for me to compensate the Air to fuel ratio other than the cars ECU.

As far is your last statement? yes the tune should fix this issue.

eagle_lex

my service advisor was dead serious when he said you MUST blow the carbon out of these motors. i thought he was joking. not sure this helps you on this topic but might help others.

stangxs

Ok after doing a little research, I'm going to drive it around for a month or so and see where it goes from there (I only drive it 2-3 times a week). I cleaned the MAF's (with the MAF cleaner) before installing the filters, double checked it sat properly, and made sure the rubber inlets (that connect to the "y" connector) was on properly, and tight fitted.

I unplugged the battery for 5 mins yest to "reset the ECU" and the light was still on right when I turned it on. If it's still on after a few weeks, I'll take it to the dealer and see what they tell me.

stangxs

And I DO push the car to it's limit at least once every times I drive it, LOL, so I'm not driving it like a granny

C43AMG

Go to Harbor Freight and pick-up one of the cheap OBDII scanners and just re-set it.

xtyper

Do you have keyless go? If so, I think you need to remove the button and start the car with the key itself to reset the CEL light.

AMG-010

Is this as well as disconnecting battery?

stangxs

No keyless go.

niceguyyy01

When you disconnect the battery let it sit 10 mins, then I use my odbII scanner to clear the code. You might have fixed the issue but the light will stay on because the code was never cleared.

obsidian05e55

You have to disconnect the +, and - correct?

AMG-010

stangxs you have me a little concerned as I have K&N's arriving today. Hopefully I won't get the same issue

stangxs

Well, atleast you know what to expect, and what to look out for. Although seeing the CEL on this car irks me, I know it's not a "problem", plus, it's under warranty

Good luck

obsidian05e55

Think i remember reading you should let them sit on news paper for a day to let all the excess oil to drain.

stangxs

Don't know what that would do. I mean, I'm sure they've been sitting in the K&N box for sometime, there was no oily residue in the plastic they were wrapped in