Here is the newest problem with my Benz- '99 CLK430.. I recently had bad gas in my car and this problem was supposedly fixed by the Mercedes dealership. It runs good most of the time. However, when I start the car I can hear a faint rattling noise. It stops after it is warmed up. Sometimes (not always) when I stop in traffic, my car shakes. It idles hard and feels like it is going to stall. I thought it was the fuel filter so I had my father change it. This morning it did it again. I stopped at one traffic light and it began to shake violently, but at the next light it was fine. My boyfriend said that he believes it may be the Mass Airflow Sensor. We have 100k miles on the car and it has never been replaced. The motor mounts have been replaced recently as well. Any ideas? Could this be a result of the Mass Airflow Sensor? Please help. Thank you.

 

Could easly be the MAF but it could aslo need plugs and wires.

 

We just put new spark plugs and wires on about 5k miles ago. I am going to try some intake cleaner this weekend. I heard that may help also. Thanks for your help..

 

Buy a bottle of SEA FOAM and put it in the gas tank it will help clean out all the old gas as well.

 

be also aware of melted/blocked catalyst.

if exhaust gas cannot freely move... then it will shake violently and lack of power.

my grandma got the same symptom whenever she controls her fart.

 

I have come to realize that warming my car up in the morning will help alleviate the problem. So now I let my car run for like 5 minutes before I leave for work and I have no problems with it. I don't know what the problem is, but the CEL has not come on and it hasn't broken down (yet). I am going on a business trip for 2 weeks, so I am going to leave the car with my dad in hopes that he can figure it out.