[CarAbuser]

Sorry if you already mentioned but does your climate control still produce cool air?

If so then if may just be the heat exchanger that's not working.

[khurmit]

Originally Posted by CarAbuser

Sorry if you already mentioned but does your climate control still produce cool air?

If so then if may just be the heat exchanger that's not working.

Yep cold air & even colder air if the ACs on. But it has worked fully once when i was testing with the car jacked up which made me think there might be air in the matrix/exchanger.

I'm kind of hoping it's the flaps (or air in the system) as both the inlet & outlet pipes get v.hot (hotter than heatsoak hot).

[eg9_dc2]

hmm im pretty sure i put a post up from my phone...stupid thing..

i was gonna say when are you gonna bleed it then? u tried it on a jack again to see if it starts working? if it does just keep it at that angle, do the ventialtion procedure a few times (with leads on so battery dont go dead) and then bleed manually too......bleed that bastard dry.lol.

also put your car back on the dis, you can test the flaps, AND you have only 2 mixer flaps tht mix/decide the temp of the air, you should hear em slightly as you adjust the temp knob hot/cold...

the temp is is decided from 2-3 different sensors inside the car....read the sensors too as you adjust the temp and see the adjust read right in general.....just to cancel thiings out....

i still dont understand how you can have a blocked core if the pipes are hot....!?

and i mentioned in the other post the climate control module......try the cheaper options first.....

[eg9_dc2]

right UPDATE:

ive been reading about the heating system and i think im officially almost an expert now llol...il send you the link for proper e90 manual if you want

you need to to jack the front end of your car up, high as you can.not on a hill... but on stands or a jack...

the reason for this and why your heaters may have started working when you jacked 1 side of the car up is..because...and no one cared to mention this before so i didnt understand,

but the radiator core is a high point in the car.air will stay stuck in the high point till it is filled manually...at a tilt, then manually bleeded/refilled at a tilt making the core fill up with water first because its a low point in the car coolant system whilst being tilted and the air moving out to the next high point in the car (water tank).

if this doesnt fix your problem mate i do not know what will...for me it doesnt make sense to be anything else...so try it asap and let us know. !

[doughboy]

But the cylinder head is higher than the heater rad by a long way. By that measure the head would be full of air and have melted by now?

Plenty of 335i owners have had their water pumps replaced, thus the system completely drained, and the system re-filled on a flat ramp no problems?

If the OPs started working on a tilt, under this theory that would mean the air had been expelled, so why did in stop working when put flat again?

Worth a try though......anything to get warm!

[khurmit]

Originally Posted by doughboy

But the cylinder head is higher than the heater rad by a long way. By that measure the head would be full of air and have melted by now?

Plenty of 335i owners have had their water pumps replaced, thus the system completely drained, and the system re-filled on a flat ramp no problems?

If the OPs started working on a tilt, under this theory that would mean the air had been expelled, so why did in stop working when put flat again?

Worth a try though......anything to get warm!

Because it wasn't vented after it started working again?!?

I'm gonna bleed it tonight - like I said, going to the local multistorey as the ramps are quite steep there. Although I do agree with you that it is strange as others haven't had this prob.

[eg9_dc2]

if you have an airpocket at the top of the heater core it wont escape it can just sit at the top while the water runs through as the top of the core isnt really low. its like having a bottle of water and trying to fill it from the bottom while water is escaping from another hole...i dunno!? i just hope it works.lol.

i think its better doing it on ramps as 1 guy said he had a really high drive....unless you go half way up the ramp so the back end stays on the flat bit

also worth a quick mention is people swapping over their inlet/outlet pipes.....it backflushes the core with just the right amount of pressure..and very hot water.....then a drain/flush after....it shouldnt affect the car as it water will still be circulating same as before.

im gonna try it on mine and the tilt bleeding. fingers crossed.

if not im just gonna do an A-Z fix of the things that control the heat. ...ie control unit, sensors, mixer blen flaps...and core. a very big bill indeed i just have the feeling it wont be fixed after.haha.

[eg9_dc2]

it didnt work for me.

gonna get the pipes swapped over i think my cores blocked..

[khurmit]

Oh no - how much did you tilt etc - thought I'd try tonight, but don't think I'll be home in time.

ARE YOU SURE YOU CAN SWITCH THE PIPES AROUND & RUN THE ENGINE!?!?!?! That just sounds like a bad idea to me, cos you'll suck any debris into the whole cooling system? I've heard of people flushing the system in reverse, but not swapping the pipes and using the car. Maybe I am being overly cautious though.

[eg9_dc2]

i tilted it pretty high using 2 trolley jacks on either side...just feel the pipes...squeeze them when you feel them they should be both too hot to squeeze for more than a second or so....mine 1 is not that hot so it will be the radiator core.

id advise you doing it at your own risk (swapping the pipes over) but yeah if it works for me, and all the debris goes back into the cooling system i suppose it will be loose and free then il do another system flush to get rid of it all...

plus the hot pressurized water will do a better job of cleaning it in reverse than normal cold water.....

im gonna try it....worse case scenario could be a popped/leaking core then i wont have a choice but to change it....risk to reward ratio for me is ok..

when you swap the pipes the function of the pipes stays the same its just the flow within the radiator is from opposite ends.

[khurmit]

UPDATE: I was right! I am more knowledgeable about the IHKA system than their own master tech!

The dealer insisted that they try to fit the part their master tech confirmed didn't exist, as that was the only way they could be 100% sure that I was right. After having it for a few hrs, they called, apologized for wasting my time, and confirmed that a UK spec E92 335i does not have a heater control valve.

They are now re-investigating for free and will be inspecting the actual heater unit to check flap movement. Result - that woulda cost me loads if I was paying!

[doughboy]

Originally Posted by khurmit

.....After having it for a few hrs, they called, apologized for wasting my time, and confirmed that a UK spec E92 335i does not have a heater control valve......

BMW dealers, donkeys? Nah

[khurmit]

car was fixed by bmw back in early Dec.

Combination of 2 issues:

1) Thermostat - stuck open so water would not get chance to heat up;

2) Matrix - clogged with "goo" due to previous owner using non bmw engine coolant;

1st the Thermostat was replaced and the hvac system began giving 50% heat - but it was very random, such as cold on your feet, hot on face, passenger side all hot except for windscreen vent etc.

went back to bmw to complain, explained I thought it was a partially clogged matrix, master tech said no chance, refused to leave unless he tried to clean matrix. when he finally did cos he knew there was no getting rid of me, he had some special adapter, attached it to the bulkhead pipes, blew in compressed air, and voila out the other end came lots of brown gunk. straight away when we tried the heating, it was roasting. I had to say it to the master tech....."I told you so".

downside is now it gets too hot and the missus is always fiddling the temp settings. plus I'm constantly using the knurled wheel cos my lenses dry out. Ha!