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Discussion Starter #1
Ok so I have noticed that my car shifts smoother after it has had a chance to warm up for let's say 1-3minutes...but i dont always have time in the AM to wait so it's as if it doesn't want to shift into second gear in the morning until I've driven it a few blocks sometimes..then the devil comes out and gives my car that super fast speed and reliability to weave in and out of NYC traffic to make it to work on time...I want to know what causes this..I only have 99k miles on it..what else can I do to fix this..I drive other people's cars sometimes and it's start....shift...and go...where as I feel I should wait out of concern

...now this shifting reaction is not constant but it does happen only in the morning...not in the Pm...

I have fresh oil/filter
Replaced trans filter/fluid/pin connector
New fuel filter
New MAF
New plugs,coil packs and wires
 

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The transmission is programmed to up-shift at higher revs when the engine is cold, so that the extra heat generated by higher revving warms the engine faster. This is normal behaviour.

May not happen later in the day because you're in a warm place or the engine has retained heat.
 

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Discussion Starter #3
Is there anything else that i can do to increase the speed of this? Instant warm? I never bought this car new...but im wondering....when this car was new did it do this too? There is something?
 

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I give cars no more than 5 mins to warm up, then I cane them so that they heat up quickly.

You may not wish to do this :)

Seriously, though, I don't think there's anything you can do to change this behaviour. As I said, it's programmed from new and I'm not aware of anyone finding a way to over-ride it.
 

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Administrator 2009 SLK 55 AMG/Founding Member 2006
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In 2002 my gf had a 230 while I had a 320. Hers would take 5 mins to warm up and act normal.
 

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Warming up

I always sit in my car for 1-2 minutes in the morning, just to let it get things moving and I just feel like it's better for the car. Even so, the first few shifts are always a bit higher in the revs. I don't really think this is a Mercedes thing, I'm fairly sure my Honda does it to.
 

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2007 SLK350 fastdawg
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Mine acts the same way, I actually had a question on the forum about a week ago mentioning the same thing. I mentioned getting a transmission flush because of the slow up shifting out of 1st when it first started up in the morning and got this same answer. I guess it is what it's programmed to be! :)
 

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I always sit in my car for 1-2 minutes in the morning, just to let it get things moving and I just feel like it's better for the car. Even so, the first few shifts are always a bit higher in the revs. I don't really think this is a Mercedes thing, I'm fairly sure my Honda does it to.
I think most modern auto boxes do.
 

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From the owners manual
"Warm up the engine smoothly. Do not place full load on the engine until the operating temperature has been reached."

"With transmission in gear range “D”, “4” or “3”, upshifting from 1st to 2nd to 3rd gear is delayed depending on vehicle speed and engine temperature. This allows the catalytic converter to heat up more quickly to operating temperatures.
During the brief warm-up period this delayed upshift and increased engine noise might be perceived as a malfunction. However, neither the engine nor transmission are negatively affected by this mode of operation.
 

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From the owners manual
"Warm up the engine smoothly. Do not place full load on the engine until the operating temperature has been reached."

"With transmission in gear range “D”, “4” or “3”, upshifting from 1st to 2nd to 3rd gear is delayed depending on vehicle speed and engine temperature. This allows the catalytic converter to heat up more quickly to operating temperatures.
During the brief warm-up period this delayed upshift and increased engine noise might be perceived as a malfunction. However, neither the engine nor transmission are negatively affected by this mode of operation.
I wonder if a lazy O2 sensor would delay the cold shift? If I recall there's one upstream and one just past the catalytic converter to monitor it's function.

I just had to replace a lazy O2 sensor on my E320 which just made me think...
 
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