W205 2.1L diesel bad interior heating
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W205 2.1L diesel bad interior heating
Hey,
I’m new here, and came with a little bit of a problem.
I noticed when the weather got colder that the cabin does not heat up very well.
After starting the car, when set to "HI", warmed air starts to blow quite quickly, but after the engine warms up to operating temp. that is lukewarm never warms up.
For example: I went to on a short 2 hour trip, maybe 6 degrees outside. I set it on "HI" and air direction to forward and legs. Blown air temp is barely warm (I tried to play with AUTO and SYNC). However, after trying to reduce the temp to 20, then again to "HI", I completely lost the warm air, it started to blow cold. Only the next day, after starting the car fresh in the morning, the "warm-ish" air began to blow again.
What could be the problem? The antifreeze level is fine, the engine warms up very quickly. Maybe someone had similar problems?
I’m new here, and came with a little bit of a problem.
I noticed when the weather got colder that the cabin does not heat up very well.
After starting the car, when set to "HI", warmed air starts to blow quite quickly, but after the engine warms up to operating temp. that is lukewarm never warms up.
For example: I went to on a short 2 hour trip, maybe 6 degrees outside. I set it on "HI" and air direction to forward and legs. Blown air temp is barely warm (I tried to play with AUTO and SYNC). However, after trying to reduce the temp to 20, then again to "HI", I completely lost the warm air, it started to blow cold. Only the next day, after starting the car fresh in the morning, the "warm-ish" air began to blow again.
What could be the problem? The antifreeze level is fine, the engine warms up very quickly. Maybe someone had similar problems?
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
I am not familiar with your model, but bare in mind:
1 diesels are cold-blooded engines and don't produce much heat, unless under heavy load
2. Mercedes cars always had lousy ducts going toward the floor, so not much heat going to the feet.
With diesels I always advise to use monitoring scanner, like ScanGauge, to observe DPF regeneration and such scanner will also give you true engine temperatures.
The dummy gauge on dash is not giving you true picture, so that would be good start.
Over the years I found MB climatronics to do very good job and had to teach my wife to stop fooling with controls, when system is on the edge of its capacity (like entering car with 140F inside).
So stop playing with going from HI to LOW. Just set the temperature to your comfort zone and adjust it by 2 degrees if you want to change it.
1 diesels are cold-blooded engines and don't produce much heat, unless under heavy load
2. Mercedes cars always had lousy ducts going toward the floor, so not much heat going to the feet.
With diesels I always advise to use monitoring scanner, like ScanGauge, to observe DPF regeneration and such scanner will also give you true engine temperatures.
The dummy gauge on dash is not giving you true picture, so that would be good start.
Over the years I found MB climatronics to do very good job and had to teach my wife to stop fooling with controls, when system is on the edge of its capacity (like entering car with 140F inside).
So stop playing with going from HI to LOW. Just set the temperature to your comfort zone and adjust it by 2 degrees if you want to change it.
MBWorld Fanatic!
Joined: Apr 2003
Posts: 1,032
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From: Northeast
2012 S350 Bluetec, 2014 GLK250 Bluetec, 2026 E350 4Matic
Just my 2 cents: My OM651 (same engine as yours) in my GLK has very hot heat, even in the coldest weather. I agree proper diagnosis is the way to go, but water pump, air in the cooling system, stuck thermostat are some random ideas.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Super Member
Joined: Jun 2022
Posts: 739
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
