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Everytime i start the car in the morning it shifts hard and at a high rpm until it warms like 5 minutes later. Anyone else had this problem. My two automatic Audi's never had this problem so wondering if its just a Benz thing. BTW Im new to the forum but have to car since new. Sorry if this is a noob question:)
 

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Everytime i start the car in the morning it shifts hard and at a hight rpm until it warms like 5 minutes later. Anyone else had this problem. My two older automatic Audi's never had this problem so wondering if its a Benz thing. Im new to the forum but have to car since new.
Its not a problem, this has been discussed before. I think the purpose was to warm up the engine and trans quicker to prevent damage from cold temps.
 

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Its not a problem, this has been discussed before. I think the purpose was to warm up the engine and trans quicker to prevent damage from cold temps.
Thanks for the quick reply. I figured it was something like that.
 

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Warms up the engine and transmission faster as mentioned above and it also warms up the catalytic converters faster.
 

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Warms up the engine and transmission faster as mentioned above and it also warms up the catalytic converters faster.
Actually, during "cold starts", it is the function of the Secondary Air Injection Pump that heats up the cats, so the system can switch from open loop to closed loop as quickly as possible.
 

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Actually, during "cold starts", it is the function of the Secondary Air Injection Pump that heats up the cats, so the system can switch from open loop to closed loop as quickly as possible.


:dunno: I have no idea what any of it means anyway. :surrender:
 

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Wheres that from the manual? I understand it as the Engine Computer communicates with the Transmission computer so it can reduce initial torque to the wheels and change shift points during warm up.
 

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It's a feature, not a bug <g>. It was designed to do this. It gives a faster warm-up at the cost of rugged-feeling shifting.
 

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:dunno: I have no idea what any of it means anyway. :surrender:
Yes this information is correct to some extent, but it is the ECU that commands the Air Pump to operate. I'm completely in the dark about the ETC having anything to do with heating up the cats. Don't worry, I don't know what it means either. Maybe I'm missing something.
 

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Where's Wolfgang when you need him!? :)
 

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I don't know about shifting hard. Mine doesn't shift hard during the warm-up period. How hard is hard shifting? BTW, all trannies are lazy when cold.
 
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