My brother gave me his '98 SLK 230 last year and everything was going well but CHECK ENGINE light came on. It used to come on for a couple of days and go off for a couple of days. But now it remained on for 2 weeks and I am concerned. I read through the forum and people mentioned O2 sensor and misfiring, what exactly is misfiring? I sometimes experience the engine stales for a second and move forward quickly when I step on my brake, is that misfiring? How serious is this? Will this cause my car to break down completely? Is this the result of faulty O2 sensor? If so, how much am I looking at if I go fix it at the dealer. Can someone explain to me? Please don't be too technical or else I won't be able to understand. Thanks.

 

The stalling could be the result of a faulty O2 sensor. Ususally it is. Basically the O2 sensor sends information to the engine and tell it the correct air/fuel mixture for the current condition. When that goes out, it can throw the mixture off resulting in misfire, stalling, and high fuel consumption.
Misfire-To fail to ignite when expected.
This just means the fuel/air mixture is ignitiing either two early or late.

If it is theO2 sensors, then it shouldn't cost much at all to fix. You can even do it yourself. But either way you have to visit the dealership to reset that light so your best bet is to take it to the dealer and have them plug your car in. Your car do have a diagnostic plug in port.

 

Thanks! That was helpful. I will take it to the dealer this weekend. =)

 

AutoZone is lending code readers, that will allow you to reset the light as well.
Did work on my VW.

 

Does Auto Zone read and erase the code for you for free? Or do they just lend you the code reader for free.

 

Try cleaning the MAFS before you take it in.

 

I paid $170 deposit and when I was done, they gave me the money back.
Mercedes is having 2 generation of readers, so the new one might be hard to find.