Only real way to check it would be to feel it....trouble is it is buried within the heater box , which in turn is buried in the centre of the dash behind all the electrickery.

You may be able to feel the pipes going into the heater matrix as the pass through the firewall right behind the engine....if they are both warm that should indicate hot coolant is passing through the heater matrix...if one is hot and the other cold it could indicate a block matrix or an air lock within it!

Thing is, they are both warm. Or lukewarm.

Leaning towards changing the thermostat. The thermostat costs the same as an hours labour in norway. So might do the trick, and a new thermostat is never bad, is it?

May it be air in the system still? Do this engine have more than one bleed screw (other bmw engines do)? I have tried parking it in a steep hill etc to no avail. I have had the low coolant/air in the system crap on my BMW E39 before, but then it god lukewarm at least. Now its ####in freezin in there.
 
Thing is, they are both warm. Or lukewarm.

Leaning towards changing the thermostat. The thermostat costs the same as an hours labour in norway. So might do the trick, and a new thermostat is never bad, is it?

May it be air in the system still? Do this engine have more than one bleed screw (other bmw engines do)? I have tried parking it in a steep hill etc to no avail. I have had the low coolant/air in the system crap on my BMW E39 before, but then it god lukewarm at least. Now its ####in freezin in there.

Had two minutes of sudden hot air from the fans today. Then cold again!
 
I can only think it is a blend motor issue....I'll have to look through RAVE and see how it works....

The BMW E38 uses two heater matrix's, one for the driver and one for the passenger. they are controlled by a Heater Valve which does fail and if I remember correctly I am sure I have seen a similar valve in the L322 engine bay...but this could be part of the Aux Ventilation system and not the heater system!
 
I can only think it is a blend motor issue....I'll have to look through RAVE and see how it works....

The BMW E38 uses two heater matrix's, one for the driver and one for the passenger. they are controlled by a Heater Valve which does fail and if I remember correctly I am sure I have seen a similar valve in the L322 engine bay...but this could be part of the Aux Ventilation system and not the heater system!

His 4.4 shouldn't havs AUX heating fitted unless he's a very lucky boy and his L322 had one fitted as an extra
 
I can only think it is a blend motor issue....I'll have to look through RAVE and see how it works....

The BMW E38 uses two heater matrix's, one for the driver and one for the passenger. they are controlled by a Heater Valve which does fail and if I remember correctly I am sure I have seen a similar valve in the L322 engine bay...but this could be part of the Aux Ventilation system and not the heater system!

See post #5 ref Heater control valve, internal leak causes short circuit and possible electrical damage to in cabin controls, how do I know, had it happen on a 04 model, fortunately only valve, usual signs are A/C starts blowin hot on one side, if not a gas leak then possible control valve?
 
Yep the L322 uses a dual cored Heater Matrix and the coolant is controlled via valves into each side of the matrix to determine outlet temperature.

As Qatar say above....no doubt the control valves have failed as he mentions.

The Hi-line system has two valves for each side of the car, the lo line system has a single valve!.
 
Yep the L322 uses a dual cored Heater Matrix and the coolant is controlled via valves into each side of the matrix to determine outlet temperature.

As Qatar say above....no doubt the control valves have failed as he mentions.

The Hi-line system has two valves for each side of the car, the lo line system has a single valve!.

Have found the valves. two of them. Have them on my BMW as well, and have fixed them before. Will give them a clean afterwards and se what happens. Could be it!

I have something called Auxiliry heating on the car. At least in the sat menu. No idea what it is!
 
Do you have working aircon?

There is a flap there somewhere as well, also if it is a genuine "Cold weather pack" car it may have the 2 heater units etal BMWs

Go for the thermostat, drain rad and refill with coolant, thats a simple job which may just fix it.

if it worked for a few minutes and them went off I honestly think it is your "Hedgehog" Regulator as mine did that exact same thing. but I had heat in the back.
It then fixed itself one cold Sunday morning just as I was about to break my back/arm and try to get 18 stone in the drivers footwell.
 
Do you have working aircon?

There is a flap there somewhere as well, also if it is a genuine "Cold weather pack" car it may have the 2 heater units etal BMWs

Go for the thermostat, drain rad and refill with coolant, thats a simple job which may just fix it.

if it worked for a few minutes and them went off I honestly think it is your "Hedgehog" Regulator as mine did that exact same thing. but I had heat in the back.
It then fixed itself one cold Sunday morning just as I was about to break my back/arm and try to get 18 stone in the drivers footwell.

Keep in mind I live in Norway. Most cars come with winterpackages as standard. To cold here in winter. Skiing is good though ;)

I`ll drain the radiator when I switch the thermostat. Anything special to do when I drain the car? All input is fantastic here!

New thermostat will be in on wednesday. I hate waiting for stuff like this.
 
Aux Vent is for when it is a hot day, you can set a time or the fans to come on and ventilate the vehicle for a set time....

On the Diesel Models they have the benefit of a Fuel Burning Heater which can be used to warm the vehicle interior either at a preset time in the control system or via a remote transmitter.

Not many petrol models were fitted with a FBH...
 
Going by a mate with diagnostics tools. Anything special to look for? What will come up of faults like this and what will stay hidden?
 
If the coolant is relatively new, just top up - if it is old, you may as well drain and refill..!!
 
New Thermostat in place. Blows a little bit better. But not sure I have topped it up enough yet. Nor do I think all the bubbles are out.

Do I need to get the errorcode deleted for the Thermostat to work like it should again?
 
If you have the MAP Cooling Fault - then clear this out!

I`ll bleed the system some more tonight, and have the errors deleted tomorrow. hopefully, that will do the trick. Will, if I have the time, try to clean the heaters valves as well.
 

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