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Hi all
The check engine light continues to come on. It's been in and out of the shop several times. The last visit was at a MB dealer. The mechanic was at a loss for what the cause was. He even called me on the phone to say that he was unable to diagnose the problem. The car was running very rough before I took it in. Cylinders would shut down while I was driving, with a resulting severe loss of power. I would turn the engine off, and then would get all cylinders back. The mechanic said he had performed several tests, but nothing seemed out of the ordinary. He went to an MB tech training class and supposedly talked/discussed the situation with his peers. The consensus seemed to be that a new Mass Air Flow sensor would cure the problem. Well, the performance is a lot better, but the Check Engine light came on a month after I got the car back. I took it into Auto Zone, where they checked the code. I think it was a code 305. The OBD said that cylinder #5 was not quite right. The Auto Zone person said that it needed new spark plugs. I had just had a new set of plugs put in when the new mass air flow sensor was installed. I did buy and install the new plugs, and the check engine light went off. However, the light has come back on now, approximately 2 weeks after I put in the 2nd set of new plugs. During the whole time, the performance seems ok, although I have a feeling that if I don't put a new set of plugs in, the engine is going to go back to the point prior to the installation of the new air flow sensor.......Any ideas of what the problem is?