ark1tech

My car has been a little lumpy at idle whether I am in P or D. It just seems to be shaking a little. Also, sometimes I get a rotten egg smell. I just got an oil change yesterday and it was still doing the same type of lumpy shaking. It really is not a violent shake, but i can feel it. Also, I did not smell the rotten egg smell at all yesterday, but I really did not get to drive too much. Anyone comments would be greatly appreciated. Thanks (2003 CLK 500 80k miles)

moondust

That is sulfur dioxide. Comes from the petrol you use - some worse than others. I always notice it at a cold start, but I think that the cat is supposed to absorb it, once it has warmed up. Maybe yours is faulty..? Or the O2 sensor(s) are bad.

Can you get your codes read?

ZEEK

What kind of gas do you put and which brand? Also the shake could be anything such as... MAF, plugs, wires, O2 sensors etc etc.

jnolte

I think if it smell rotten the catalytic converter is bad and could be clogged, check them