My 1993 SL500 runs great, I just waxed a 5.0 Mustang the other day when my wife and I were out with the top down, my problem is that it does not idle as smoothly as I think that it should. I am the second adult owner and it has been Dealer serviced it's whole life and pampered. Can anyone tell me what to look for?, everyone that I have talked to says to forget about anything internal in the engine, that the internals are good for 100 to 300K and to look for somthing like spark plug wires. The car has only 71K on it and looks new. Any help will be appreciated. Dave

 

replace plugs first, BOSCH only! if that don't solve the problem inspect or replace distributor cap and rotor. plugs should be replaced between 35 & 50k. if u have a benz shop you trust, you might want to have it analyzed if the plugs don't work. that can save a bunch of part changing.

 

Thanks for the fast reply and I will do exactly as you say, do the plugs first and then look for the cap and rotor, it is great having so many people versed in this car to talk to, I am new to the Merc and am just learning but it is an amazing car. Dave

 

ALERT......Do not waste your money on new plugs, wires, caps, cam sensors, etc. It will not, remember NOT fix the problem. This has been happening to mine for 6 years now, believe me money won't solve it...well at least my pocket book. It has something to do with a little cam gear (MB from Germany tells me).
If you do figure ot out I would love to hear from you!