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Recently i've notice that all my passenger side vents is blowing cold ( slightly worm ) air , when drivers side is nice and hot ,i can barely hold my hand on . So far i've tried to bleed the whole system ,than heater matrix it self whit no luck . The car is running fine, engine temperature sits at 90c , not loosing any coolant or oil .

Any ideas welcome

Maybe something, like a flap, is physically blocking the off side of the heater core so that the heat favours the near side as it hits the distribution plenum? It wouldn't be the internal piping, as they run back and forth transversely, such that any blockage could not favour one side significantly. Or maybe a flap is stuck such that lots of fresh air is mixed in only on the off side?

I don't know how the flaps are arranged, but it seems that one of them must not be operating correctly.

Either that or you have the very rare optional dual control HVAC and you just need to adjust the passenger's temp control.

Marius wrote:Recently i've notice that all my passenger side vents is blowing cold ( slightly worm ) air , when drivers side is nice and hot ,i can barely hold my hand on . So far i've tried to bleed the whole system ,than heater matrix it self whit no luck . The car is running fine, engine temperature sits at 90c , not loosing any coolant or oil .

Any ideas welcome

isnt there something in the manual about "setting" heater preferences ?

ok page 17 in manual /
examples of key memory
" automatic setting of the automatic air conditioner to the respective user's preferences when the car is unlocked "

on the previous page it also says

"depending on the configuration of the memory functions, operation of your vehicle may differ from description's given in handbook & please remember when selling your BMW to have all memory function's returned to original standard "

unless your's has no memory function facility it could be worth investigating before you tear out the dash

aMy E85 used to roast my clutch foot in crawling traffic and i always had to turn it down in traffic to preserve the skin on my left foot. however on a more closely associated note, a friend with an E85 always said that the drivers side was hotter with better flow than the passenger side. he partially blocked the drivers side to aid the passage side.

try banking off the drivers side to see if it affects the air distribution or it could be as has been suggested an air distribution flap.


Dario

looks like there is only 3 actuators

1 for air blend,
1 for recirculation
1 for keaimetecs ?

dario wrote:looks like there is only 3 actuators

1 for air blend,
1 for recirculation
1 for keaimetecs ?
[img]http://i66.photobucket.com/albums/h243/ ... er.png[img]

they all working , moving up and down also fount and replace the filter on the passengers side , even disconnected battery for 20min, no luck

Guess i found the problem . On idle or between 1000-2000rpm heater is blowing cold(warm) air, but when i keep revs at 3-4k rpm it's blowing hot as it should

I have feeling that water pump is on the way out , i'm right or there is something else i'm missing

could be an airlock, my compact did the same thing. The only way I cured it was to provide pressure to the tank I think garages have special tools however what I did was buy one of these http://www.tesco.com/groceries/Product/ ... =267832188 5L water bottle the cap end is about the same size as the filler cap and fits quite snug over the top. Get some gaffa tape a wrap a little of it around the end of the bottom with the cap off to provide some desgree of seal. Get someone to rev the engine and then the bottle upside down quickly turn it upside down and hold it over the filler hole. It doesn't have to fit perfectly there will be some leakage but what you will find is when you rev the engine up bubbles go up to the top on the water bottle and the water quickly disappears inside the system when you stop reving the water remains at the same level. The bottle also gets 'sucked' and contracts inwards. I kept doing this by filling the water up again and again until it did it no more. Problem solved.

thanks, will try that and let you know how it went

thanks to yg54sg , took about the hour but is working now

Well done

Result

Marius wrote:thanks to yg54sg , took about the hour but is working now

happy days when a problem is sorted & even better when its cost you nothing but time

Did you have any problems doing it?