K&N filters installed, CHECK ENGINE LIGHT ON
 

Hey guys,

Yesterday night I finished installing my K&N filters, I bought these brand new and simply dropped them in, and re-installed the covers back on. I put about 10 miles on yesterday and today about 5 miles and my check engine light went on after hitting the throttle down a bit harder. The car felt strong and still does, however the check engine light appeared. Anyone know how to reset the computer or had this issue before? I'm not too worried about it since I will be taking the car shortly to Eurocharged for some Headers and heat Exchanger work, so the guys there can check it out. I just want to make sure everything is ok.

Thanks

KAMIL

Assuming you installed the reusable K&Ns, your MAF sensor is probably fouled with oil off the filters. Do an OBD II scan and check to see if codes P0170 and P0173 appear. You can get some CRC MAF cleaner at an auto parts store and clean it. This type of filter (wire mesh) can allow particles large enough to eventually damage the sensor and it will need to be replaced.

Of course, there are many other things which trip the CEL and it could just be a coincidence. Again, a OBD II scan is recommended.

How expensive is the MAF? is it worth changing if I will mod the car in the near future?

Thank You for chiming in

The SL55 doesn't have a MAF.
You need the check/clear the code to get the light off.

??? no MAF that is wierd, I will go check out the code hopefully sometime this week.

Do you guys know how you reset the computer??? I know there is a way to do it, so that it resets the memory of throttle response and so on, but I'm not sure where to find it.

I have K&Ns in my SL and have had no problems. However, when I installed them in my E550 the check engine light activated within five miles. The codes indicated I had bad oxygen sensors that were replaced under warranty. Granted it's a different engine but the outcome is the same. This is the first time I've ever had a "problem" with K&N's in all the cars I've owned.

Yes, there is a MAF in the air duct just after the air filter. The place it is on most cars. Since I don't have the car in front of me, I checked EPC.net which shows the MAF on the AMG engine.

You can read the codes and clear the CEL with an inexpensive scanner. Places such as Harbor Freight and auto parts stores have them ($50-90). Connector for scanner should be under dash on drivers side. It may have a plastic cover to flip down.

However, unless you 'fix' the problem the CEL will come back. Also, a bad or disconnected MAF can result in a rich mixture which will cause the catalytic convertors to overheat and melt down. :eek:

Good luck.

Not on the SC AMG engine in the SL55. The SC engine uses a MAP sensor. My NA CLK55 has a MAF sensor so you are correct on some AMG engines have one..Just not the SC engines.

My apologies you are correct. Sometimes the illustrations on EPC.net are 'one size fits all'. When I doubled checked with some third party suppliers I was unable to 'buy' a MAF for the model in question.

There is a reset button on the right or left hand side of the instrument
cluster, sometimes it has the letter...R...on.
This seems to reset most things.:y

Recheck your install. You may have knocked a connector or hose off changing the filters.

I have not reset any CEL with any buttons in the cabin. You can reset the CEL with a scanner but not clear all the codes without a Star tool. It's amazing what codes gets set with one fault.

Most auto parts stores can read the code set and clear the light unless you have a hard fault. A good independant shop should be able to get you back on the road if you don't wish to deal with the MB shop.

Check for any loose hoses on the back side of the filter boxes. Perhaps the left side.... an air filter swap should in no way illuminate the check engine light on your vehicle. :-)

That's the ticket! Look for the small hose that could be disconnected below the intake box on the drivers side. US Model.

ANy more feedback on this, I keep hearing on diff. forums here K&N fouls stuff or it doesnt..what about BMC?

I have been using K&Ns on all my cars, as well as our client's car, and as long as they aren't over oiled, or installed wrong, they work great. I have never had any issues whatsoever.

Vac hose in the back slipped off. THANKS FOR THE HELP GUYS

hehehe FAIL>.:smash:

best case scenario just happened here. this could've gotten ugly lol :p:

This is a first for me, sl55 uses MAP... would i be correct to assume all 55k engines use MAP as well?

55k engine use pressure sensor mount on the distrubitor intake pipe.. measure charged air.. similar to map/Maf...

I think in general to many”out of the blue” answers are posted from people without any clear knowledge off these cars.

If a person has a problem with his car, please post if you really have knowledge or real world experiences on this otherwise don’t.

There is no issue with K&N or Green oiled air filters what so ever, this is just gossip talk from the past.
:bow:

might have been oiled too much from factory check maf