White Smoke from front-end of W202 220 CDi

[howblum]

Hi
I have white smoke that intermittently comes out of the offside front below the front bumper and by the wheel. It only seems to happen when the car is stationary and with the engine on or off (it gets blown out by a fan when I turn the ignition off). Sometimes it's a wispy smoke, other times more dense, but is accompanied by a whiff of sweet-smelling diesel. I think it only happens when the weather is cold! A local MB independent suggested it might be the cat. failing, but I was hoping that you guys (or gals) might have other ideas that don't involve spending loads. Any suggestions would be most appreciated.
The car is year 2000.
Thanks

 

[Mike J]

Morning Howblum
On my 210 that is the location of the aux heater which is diesel powered with an exhaust (small flexible pipe) which points down just in behind the bumper. Mine is controlled by a switch alongside the ashtray and apparently will only operate when weather is cold (below 5deg I believe).
I say apparently as I have never been able to get mine to work.
Regards
Mike

 

[television]

I cant think of anything else other than an AUX heater

 

[howblum]

Morning to you too. Thanks for the replies, MikeJ and Television. It makes sense, so where is smoke being produced in the first place that the fan then blows out?

 

[David Nock]

Morning Howblum
On my 210 that is the location of the aux heater which is diesel powered with an exhaust (small flexible pipe) which points down just in behind the bumper. Mine is controlled by a switch alongside the ashtray and apparently will only operate when weather is cold (below 5deg I believe).
I say apparently as I have never been able to get mine to work.
Regards
Mike

I have a friend in Wales with one of these Aux Heaters and he's asked me to enquire of this learned forum why his doesn't work. Maybe the 5 degrees is the answer.
For my benefit, never having encountered one, how do they work? Is it some sort of compressor powered device or is there a diesel burner? Surely not the latter?

 

[David Nock]

I've done a search on Aux Heater and I read that my friend will have a small diesel 'unit' near the front O/S wing, possibly to boost the car heater (C220CDI W Reg).
A further question - can it be used with the car stopped? ie turned off, or is it a supplement to the main heater. If it only works below 5 degrees, why is a switch control needed?

 

[Mike J]

David
As far as I have been able discover the unit is a stand alone diesel burner that warms and independently pumps water around the heater matrix only. According to my information the unit will only work if the outside temperature is below 5degs + the water temperature is below a preset limit (sorry don’t know what that limit is) and the switch (in my car) alongside the ashtray is set with the light off.
As to why it needs a switch control that is a very good question that I have absolutely no answer too as mine has never worked so I have not given it to much thought.
If your friend does manage to get his working please let me know.
Mike

 

[rf065]

A local MB independent suggested it might be the cat. failing

Thats one independant I would not let near my car if that was his advice.

Russ

 

[alec2]

These heaters are diesel powered and are intended to warm up the engine more rapidly when it is cold outside.

They are fitted to diesel cars because the engine is more efficient which means it produces less waste heat so it and the heater will warm up slowly.

On the w203range they come on if the engine is cold and the outside temp is below 7degC. They can be programmed to stay off.

On some models they can be run with the engine off, I believe they are fired up from the remote door key! So your car can be warmed up before you go to it.

They are smaller versions of heaters fitted to ambulances, coaches and boats which all can produce white smoke, usually from lack of use and fouling up . Try using it more often it will probably clear up.

Alec

 

[howblum]

Thanks to you all who have responded to my question - your knowledge is invaluable.

 

[Cnics]

Try using it more often it will probably clear up.

Alec

The problem with this is, when it doesn't work above 7degrees, this means you can't power it up over some of the months.