I have noticed several early morning start ups with annoying episodes of 10 seconds or so of engine missing. Sounds like rich running missing? I have become aware that missing don't always occur, only occuring on mornings when the car had been cold started and pulled it into the garage the night before. Car only allowed to run less than a minute when pulled into garage for the night. (not long enough to warm up).

My early theory is that the enrichment for the morning start is somehow being enriched TOO MUCH due to the cold start (but no warm up) 7 to 8 hours earlier when the car was put away in the garage for the night.
Does the enrichment start off with a base of wherever it LAST RAN ?
It is summer here now, 60F at night, but similar episodes have happened even when nightime temps were lower this past spring.

Anyone else have an idea?
70K miles, Car runs fine and does not show no other signs of trouble.
OK mileage (aggressive city use=16mpg; Highway, 70-80 mph cruise= 21mpg-22 w/o air)

DanielW

Check your distributor caps and rotors. Sounds like the way one runs with corroded caps. If they look green inside they need to be replaced.

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Mercedes Benz Master Tech - Retired

Every morning I have to start the car for 30 seconds to 1 minute to 'warm it up' or else the car goes very slow w/ high rpm until it has warmed up fully.

You can consider your "problem" normal, as Mercedes has an upshift delay until the vehicle warms sufficiently, to increase effficiency by bringing the cats and O2 sensors up to temp faster.

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Don't ask me, I'm a shop-owner by default

thanks.. it only started happening recently...some mornings it will just take off and others i just wait for it to warm up..

also.. you have any opinion on this thread:

2 problems with my s500 that are ANNOYING!

its the locking problem.