Aircon blowing cold on left but warm on right side vents E70

[Leslie]

The left vents blow cold and the right vents blow at normal air temp which has been warm this last while which is why its become more noticeable although I think it has only started recently.
The most likely cause seems to be a failing heater control valve which sits on the passenger inner wing , there are some very cheap ones on ebay Circ £25 new which I will be avoiding after buying a dud throttle valve last time which didn't work for my dpf issue. Going of genuine ones on ebay it seems the dealer would need 400 quid ! for a plastic valve but Autodoc has a Bosch one for a more palatable 100 delivered.

In other news after getting our ds3 mot yesterday I took a late cancellation and get the x5 mot'ed last night ..Result as otherwise the next date was mid September (waiting times are going back to months here in Northern Ireland again for the umpteenth time ) That's 3 of the fleet through mot in 7 days

[Leslie]

Well I changed the heater control valve on the passenger inner wing , didnt take too long 3 pipes but it doesn't seem much better .lost coolant has been topped up , if i put it to max its certainly hot and min its a little below outside temp while left side is cooling the air but it isn't brilliant either.
Im beginning to think a flap motor isn't moving now but I think that is a can of worms id rather not open. Willcheck codes later..
Its been a bad day found my 205 gti has sheared its alternator tensioner bolt in the pas pump and now ive jammed a torx bit between the inner wing trying to temove the alternator with a ratchet spanner on the torx bit as no clearance so now the ratchet will only go one way and we are stuck

[Leslie]

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Took the vlave apart nothing looks broken

[Leslie]

Got codes E723 and E729

E723 is no message condensation sensor apparently this lives behind the rearview mirror so I will have a look tomorrow

E729 is no messsage auto air recirc and is the plug on the pollen filters which I left off when I changed the injectors ,now plugged in and cleared and nothing to do with the current aircon to one side fault.

[X5Sport]

Are the solenoids actually good? As in, if you put volts on them does anything happen? The disassembled one has corrosion on the core which might jam it in the bore maybe?

[Leslie]

I've a new one on now so it doesn't really matter , its definitely possible one solenoid has failed but they are free moving ,if would fail open as its spring loaded so heat all the time but I was more getting room temp all the time ,one of the little screw heads has snapped of putting it back together so its faulty now alright lol I unplugged the condensation sensor on the screen ,had cleared codes already but it came back , will clear again now its unplugged .
This is quite expensive to but a genuine one(about £160 ) and I'm not convinced it would only stop aircon to the drivers side so I'm not keen on buying it , I could buy a Chinese copy cheap but we all know how that often goes

Trawling the net does not show anyone with the failed condensation sensor having my issues that I can find and the sensor seems a common failure.An ebay seller has sold 450 secondhand ones , if they are really fail that often I wonder how many of the ones they sold are actual duds ,if they are cheap people don't bother to return them

[Leslie]

Today if I set the climate in auto to 25c it still blows cold only going warm when you put it to 28c max , I'm beginning to think the climate unit is faulty .

[X5Sport]

If I remember rightly, there’s a temp sensor in the control panel itself behind a little grille? Is that free of detritus?

[Leslie]

Im guessing there are 2 but maybe not , i will have a hoover and see

[Leslie]

Hoovered the vent not much came out and I think you are right just one side has a vent , still the same auto doesn't seem to know what its doing but you can have hot either side when turned to 28c but nowt below that and turn the left down to aircon temps but the right will only go to outside temp and not aircon . With the change in temps id say the new heater valve is working fine , they are spring loaded closed so if it wasn't opening there would be no heat .
Starting to think the heater valve has shorted and taken something else out in the process. every control does something just not whats asked Have ordered a replacement climate unit ,loads about and they are cheap just so many variants and realoem isn't its usual helpful self though I think they are mostly compatible and I will only know what's fitted when I see the back of it.

[Leslie]

Climate control module changed , still the same, warmer on the right and the left that was cooling isn't doing much now , guessing I've a leak ,no doubt behind the dash
The module was exactly the same part and luckily cheap too I hate slightly old cars

I will plug that old valve in another day when the car is cold with out the pipes on and see if it actually works

[X5Sport]

If you had a leak, it would be showing up surely? You’d be losing coolant as well. Do the wires check end to end?

[Leslie]

Im talking about an aircon gas leak now x5sport sorry for confusion , its.not cooling either side now and there is a faint hissing as soon as the snowflake button is pressed which stops when it is switched off. There is no coolant leak I just want to see if the.old valve was actually working when asked as I replaced it but nothing has changed.

Several issues going on here I think , I swapped the climate control as I was only getting cold air on the left despite replacing the water valve being replaced which is the usual cause of this. The aircon has been getting less cold this last week or so anyway which would point to a leak .
The only code when checked was for the fogging sensor which is about £150 but I'm not convinced it will make any difference
I will check evap temp tonight as was 3c last week.

[X5Sport]

Right, gotcha. If the AC goes to a low gas state then the compressor clutch locks out as well I think. If it’s not cooling then a leak or compressor issue definitely comes on the radar. You used to be able to get pressure gauges from Halfords (I have my E53 one somewhere) that might tell you quickly what the pressure in yours looks like. The E70 probably has the later gas, and I’m not sure if the fittings are the same as I’ve not touched the E71.

[Leslie]

I had a look tonight and the compressor is cutting in and out if the snowflake button is pressed so that suggests its not low in gas despite what I thought. The evaporator temp though is now 28c so it ain't doing any cooling , was 3c last week so something has changed ? How can the evap temp be 28c with a running compressor ?

I read that the evaporator interior temp senor if giving a false cold reading it can cut the aircon but it reading 25c which is correct , shame as this is easily accessible . The left and right air vent temps are both the same so are reading correctly too.

that bloody fogging sensor comms code is all I have to go on I'm not convinced (yet)

Doing a bit of googling and I'm now thinking the expansion valve is faulty and is not letting gas into the evaporator ...