2001 V70 Hot air in driver side footwell

stickymatch · Post by **stickymatch** » 24 Jun 2014, 22:29

Hello,
My 2001 v70 has developed an annoying problem. Whenever the sunroof or a window is open I feel hot air coming from the driver side footwell. The hot air is not coming from any vent. In fact I can have the A/C on full and cold air comes from the vents but I still feel hot air from the footwell area. The car has a manual climate control module and other than a surging fan (resistor pack issue?) works perfectly. Any ideas where to begin trouble shooting this issue?

Post by **abscate** » 25 Jun 2014, 04:58

It sounds like there is an opening in the firewall and you are getting hot air from over the exhaust manifold coming in. Make sure the gasket for your heater hose coupling is in place, I think that is the biggest hole there.

stickymatch · Post by **stickymatch** » 26 Jun 2014, 18:25

Thanks for the suggestion. I checked all gaskets in the firewall and they are ok. I think I have found the source of the hot air. After removing the trim panels around the driver side footwell and driving around a bit the hot air is basically radiant heat from around the heater core finding its way into the footwell area. I assume since the core always has hot coolant running through it there is nothing abnormal. I noticed when removing the trim pieces that they were not seated correctly and perhaps the fix is as simple making sure the pieces fit together correctly to prevent the ambient air from being drawn into the cabin. I think i will try adding some insulation around the heater core before reassembling the trim pieces.

Post by **abscate** » 27 Jun 2014, 13:21

The heater core is always hot, correct. If the trim is out of place, I think you would notice the heat load as you note.

stickymatch · Post by **stickymatch** » 25 Jul 2014, 14:55

Root cause found and fixed! The previous owner had the heater core replaced and it looks like whoever did the work cut away part of the surrounding vent duct work ( i guess to make it easier to access the core) but did nothing to replace the cut away parts thereby allowing hot air to escape from the around the heater core. I used high temp HVAC aluminium tape to seal the heater core and no more hot air is escaping when I open a window or the sun roof.

rtfact32 · Post by **rtfact32** » 04 Aug 2019, 21:50

Thank you SO much! This solved my issue as well. My V70 is on it's second heater-core (265k and counting). I've had the car just over 2 years now and that warm breeze really bugged me...