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Once in a while my c280 idles a little rough, not much but just a little. My shop mentioned once that this might be related to the coilpacks. Anyhow there is no error code present nor is the check engine light on.
If one coilpack is going bad wouldn't there be a misfire code for one of the cylinders?

Now when it is cold the car has the following issue. It starts just fine, runs a little on higher rpm and after while it drops to normal rpm which is normal. If you now shift into D or reverse (it's automatic) the car goes out. This happens if the car is cold and the outside temps are around freezing or lower. If the car warms up, sometimes 5 min sometines 10 min depending on temps it does not go off when you put gear in.
Might this have something to do with the coilpacks? if yes how do I know which one to replace since there is no fault code.
Almost sounds to me like something else other than the coilpack.
 

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1997 C280 (Cambria).
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Once in a while my c280 idles a little rough, not much but just a little. My shop mentioned once that this might be related to the coilpacks. Anyhow there is no error code present nor is the check engine light on.
If one coilpack is going bad wouldn't there be a misfire code for one of the cylinders?

Now when it is cold the car has the following issue. It starts just fine, runs a little on higher rpm and after while it drops to normal rpm which is normal. If you now shift into D or reverse (it's automatic) the car goes out. This happens if the car is cold and the outside temps are around freezing or lower. If the car warms up, sometimes 5 min sometines 10 min depending on temps it does not go off when you put gear in.
Might this have something to do with the coilpacks? if yes how do I know which one to replace since there is no fault code.
Almost sounds to me like something else other than the coilpack.

I dont know nothin bout coilpacks. But if you changed the spark plugs since you bought it perhaps they arnt gapped correctly? If they are even a little off it will change your compression and in the cold your compression changes even more until the engine warms up. And in neutral or park there isnt really a load on the engine, so when you shift into gear its putting a load on the engine so if the compression is off it could be causing it to stall. Just my thoughts.

I think bad compression is what would be causing it to idle rough but not register as a misfire (since it IS actually firing). However whats causing it to be that bad I can only think its either the a/f ratio or spark plugs. Could very well be the coilpacks.

Engines in general dont like the cold haha. I dont like it either. Some guy I went to high school with said his ford escort got better compression in the cold, but I think he was full of it. I think pretty much every engine will have worse compression when its cold. Thats why you generally use more gas in the winter. That and running the heater all the time.
 

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2015 C300 4Matic, 1978 240D
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Engines in general dont like the cold haha. I dont like it either. Some guy I went to high school with said his ford escort got better compression in the cold, but I think he was full of it. I think pretty much every engine will have worse compression when its cold. Thats why you generally use more gas in the winter. That and running the heater all the time.
A modern computer controlled engine should run exactly the same in the cold as it does in the heat. A carbureted aircraft engine produces much more power in the cold than the heat...

I'm having a similar problem - for the last two winters my car has had the check engine light come on as soon as it gets cold out and idled roughly. The only code is "p0110" which doesn't seem to make sense, but my guess is the MAF since mine has never been replaced and everybody seems to have trouble with it.
 

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1997 C280 (Cambria).
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A modern computer controlled engine should run exactly the same in the cold as it does in the heat. A carbureted aircraft engine produces much more power in the cold than the heat...

I'm having a similar problem - for the last two winters my car has had the check engine light come on as soon as it gets cold out and idled roughly. The only code is "p0110" which doesn't seem to make sense, but my guess is the MAF since mine has never been replaced and everybody seems to have trouble with it.
A computer cant keep a cold engine warm. If the engine is cold enough, its compression will change until it warms up. Happens with all engines.
 

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1995 C280 (165K mi)
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it's not likely that your problem is a coil pack. MAFs have been known to cause lots of weird problems like this. disconnect it momentarily and see how the car behaves.

what year is your car, location and miles. update your info before you post any more.
 

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Most cars use two temp sensors. One for the computer and one for the guage display. Not sure about Mercedes, but you could very well have a 'funny' sensor.
 

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95 c220
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I believe you use more gas in the winter because of the expansion rate of gasoline. On a hot summer day the gasoline in the tank expands and produces more vapors and pressure in the tank so less fillups in summer then winter. Also, running the heater should not use more gasoline. Running the a/c in the summer should burn more because of the compressor running more,thus putting a drag on the engine. Drag from open windows is another topic.
 

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1995 C280 (165K mi)
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I believe you use more gas in the winter because of the expansion rate of gasoline. On a hot summer day the gasoline in the tank expands and produces more vapors and pressure in the tank so less fillups in summer then winter. Also, running the heater should not use more gasoline. Running the a/c in the summer should burn more because of the compressor running more,thus putting a drag on the engine. Drag from open windows is another topic.
what does this have to do with his problem?
 

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i had many of same issues on my car and it pissed me off bad i did so much to try and fix the issues finally i got air temp sensor for 20 usd and the water temp sensors 20 and 8 and 8 there is three. now my car runs like a champ when i start it up thank god cause it was the worst before. i would seriously change these and then see if it helps go tot autohauz usa website cause these parts can be hard to find good luck let us know how it goes also i did my maf cps egr o2 sensors plugs wires but they didnt help just the temp sensors
 
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