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Can't/won't say that this is a recent development. Might have more to do with the fact that it's now summer and I tend to drive barefoot, but there's an awful lot of heat hitting my feet. The temp gauge seems normal...maybe 190? Is this normal?
 

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Do you have your AC on and air vent towards the foot well? If yes, then that's where the heat is coming from..
 

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I'd guess that depends on your HVAC setting and the temperature inside the car.

If you set your HVAC for 65 and drive with the windows down when it is 64 then your feet will get hot.

Can you be more specific about the issue?

d-
 

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Go get an emissions test, could be a bunged up cat.
 

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Discussion Starter #7
I'd guess that depends on your HVAC setting and the temperature inside the car.

If you set your HVAC for 65 and drive with the windows down when it is 64 then your feet will get hot.

Can you be more specific about the issue?

d-
>>>

HVAC is off. Temp gauge is normal. I feel hot air around my feet.:dunno: It may be there all the time. Try driving barefoot and let me know.
 

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It isn't. When the HVAC is off you should get little / no air blowing.

Does your re-circ button work when the HVAC is on? You should be able to hear it switch from recirculating air to outside fresh air.

I'd guess that either your recirc actuator, your floor actuator, or both are not functioning.

d-
 

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I just noticed this issue today. It's about 60 outside...
AC is off, and the center wheel is set all the way to blue dots (cold).
Fan was on auto, and temperature was set at 70, is that normal for foot to be blowing hot air when vents are blowing cool (outside) air?
 

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Failures of HVAC seem to occur in the E39 community, but don't get seen on here so much.

I suspected my dual heater solenoid valve for a while for random melted faces and feet, and INPA told me last night there was short-circuit detected in the aux water pump, which depending on what vintage of E39, is integral to the unit, or nearer the radiator???

Did have some hope though, the part isn't cheap, but worth my checking the wiring, short circuit might just mean some old and brittle wiring down there. Here's hoping.:)

Is you hot air blowing all the time, or does it come and go, and is it always on your feet, or can it move to the face vents too? INPA can show you where all the vents and flaps are, or where it thinks they are (very cool). You might have a stuck flap (ooer).
 

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Sorry, I'm not sure what INPA is.

It seems to be there at the foot well all the time. If I turn it to manual, and use only face or windshield vent, it seems OK. Now I'm wondering if I have a bigger problem, or it's just cold out there, and the footwell heats up by it self.

If when I turn on the AC, and footwell is still blowing hot air, I will know it's for sure wrong. does that happen according to what you mentioned? (solenoid, etc, which I didn't understand).

Thanks again.
 

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Probably best before I confuse the issue any more is to try and sort the issue I have, it's perhaps not the same as what you are experiencing.

My issue is that I can be driving along and all of a sudden one or more of the vents starts blowing hot air, as hot as it can it seems, and only playing around with the direction of flow can stop it sometimes.

If you look at part #1 in this diagram : RealOEM.com * BMW E39 M5 Water valve/Water hose that looks like a small factory, this device modulates the flow of coolant to either side of the car, hence the ability in the cabin to set both sides to different temperatures. I felt this has failed, having done some reading on the problem. It's not cheap but looks a doddle to change, only issue being it's deep in the engine bay but hey. Can't have everything.

I referred to : E39 540 - help with air con - drivers side! for my information. You can see this part can get really gunged up over time and then the solenoids fail to move properly or the pump can fail or the fins break and it becomes less efficient.

The main thing is we have a complex HVAC system (Heating, Ventilating, and Air Conditioning) which is great when it works correctly but is a pain when things start to go amiss.

INPA by the way is a BMW diagnostic tool via a laptop (or PC...) that connects to the car via an OBDII cable, and can check various systems around the car, and for faults in various modules. This checked out for the solenoid jobby I had been suspecting when it had logged a fault for the aux water pump (part of the solenoid valve) for a short circuit. The part may be faulty or it may be the wiring.

Google INPA to find out properly what it and what it can do, I've had it but a short while and it's great for tinkerers and people who want to know exactly what their car is doing. For the HVAC system, it shows the positions of the various flaps in the system and the temps picked up by the appropriate sensors, so you get a better picture of what is and isn't working :)
 
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