Hi all

when recirculating air is selected I get good airflow, when I use fresh air, it is minimal to nil.
I have replaced the cabin filter (even running with no filter makes no difference)

I have checked the air intake (outside of car below windscreen) and it’s not blocked.

I have tried a flap calibration (holding AC and front blower buttons), which made no difference. 

 

I noticed when I replaced the air filter with the filter cover open and had it on fresh air mode, it sucked air through where the filter cover goes, and when I put it back on, it sucked it closed like a vacuum, as it tried to get air from somewhere- until it sucked it closed it blew air when in (falsely, due to cover being open) fresh air mode. So something isn’t open/clear between the air intake and the cabin filter box.

is there a separate fresh air actuator or something that opens the fresh air flap at the same time as another that closes the recirc? Rather than one that just changes from recirc to fresh? As soon as I change to fresh air, I hear some flaps move then suddenly the pitch of the fans increases (like under stress due to no air flow).

 

if there is an actuator, is that easily accessible and fixable (moderate level of mechanic here, at best 😃)?

 

I have an ODB2 fault code reader and will use that later but last time I ran it, it had no codes. But my wife currently has it in her car so can’t check until this evening. 

 

many thanks!

Its either going to be a blocked air intake (located in the windscreen valance) or the flap motor that switches between fresh air / recirculation air has failed (and its permanently on recirculation mode)

Just now, varaderoguy said:

Its either going to be a blocked air intake (located in the windscreen valance) or the flap motor that switches between fresh air / recirculation air has failed (and its permanently on recirculation mode)

Thanks

yes I checked the air intake as per post, and that’s clear. 
but the recirc to fresh air thing- is it one that switches, if so, why does it blow on recirc but not fresh? Seems like something else blocks the recirculating air when switched to fresh. Are there two actuators?

Not switches - motor flaps - part of the heater matrix box.  I think there are two flaps - one in the fresh air intake and one that redirects airflow around the car.  One of those has probably gone open-circuit and has ceased (although it should show up a code).

10 minutes ago, varaderoguy said:

Not switches - motor flaps - part of the heater matrix box.  I think there are two flaps - one in the fresh air intake and one that redirects airflow around the car.  One of those has probably gone open-circuit and has ceased (although it should show up a code).

Thanks. I’ll plug the code reader in later.

 

if it’s that, is it an easy fix or does the whole matrix need replacing?

Probably the matrix needs taking apart....not an easy job, but not impossible either.

Recirc flap motor is above the pollen filter, shown in the diagram here as item 18. Diagram shows a LHD car, so in RHD it is probably at the left/passenger end of the dash instead. Possibly accessible via a removable end section?

Car Parts Catalog - LLLParts

Edited 19 November, 20241 yr by Breezy_Pete

3 minutes ago, Breezy_Pete said:

Recirc flap motor is above the pollen filter, shown in the diagram here as item 18. Diagram shows a LHD car, so in RHD it is probably at the left/passenger end of the dash instead. Possibly accessible via a removable end section?

Car Parts Catalog - LLLParts

Great thanks. I’ll take a look and see if I can manually move the flap

Be aware that there is another version of the cabin A/C stuff, Denso rather than Valeo, which has a separate diagram page, with different part numbers. 

Denso version

 

I seem to remember that knowing which system your car has is not totally straightforward, and probably involves looking at the part number label on e.g. the blower motor.

Just now, andyz0 said:

Great thanks. I’ll take a look and see if I can manually move the flap

You probably won't be able to with that motor fitted, or not without damage anyway.  See if you can see it first!

55 minutes ago, Breezy_Pete said:

Be aware that there is another version of the cabin A/C stuff, Denso rather than Valeo, which has a separate diagram page, with different part numbers. 

Denso version

 

I seem to remember that knowing which system your car has is not totally straightforward, and probably involves looking at the part number label on e.g. the blower motor.

You probably won't be able to with that motor fitted, or not without damage anyway.  See if you can see it first!

I struggled to see much, but took a video of the flaps moving (starts in recirc, then fresh and back to recirc- you can hear pitch change). I could be wrong but looks like the one closest moves but the far one doesn’t- it says valeo on it. Assume the far one is the broken clean air one. Looks a right pain to get to!

video is too big to upload so here is a YouTube link: 

 

Took screenshot 1 of it in recirc, screenshot 2 in fresh air (the far flap doesn’t move)

Also just went back in and was able to gently poke the far vent with my hand and manually open it, so I do think that motor is shot. I opened it a tiny bit so some air can come through but when recirculating air is on, it will preferentially take mostly air from the wider open flap. 

Or does one motor operate both flaps?

22 minutes ago, andyz0 said:

Or does one motor operate both flaps?

I didn't look that closely at the parts diagram, which doesn't even show the flaps, but I think there's only one motor up there,  yes.

6 minutes ago, Breezy_Pete said:

I didn't look that closely at the parts diagram, which doesn't even show the flaps, but I think there's only one motor up there,  yes.

Thanks. The far one might have popped off the teeth of the motor or something. It’s having its mot tomorrow so I’ll see what the technician says 

Is there a removable piece of trim at left-hand end of dashboard, visible with door open? That may give you a view of motor and cogs.

3 minutes ago, Breezy_Pete said:

Is there a removable piece of trim at left-hand end of dashboard, visible with door open? That may give you a view of motor and cogs.

Yeah I did take that off but I think the motor is too far back (fuse box in the way). I’ll take another look in the morning when it’s light. Also my fault code scanner is due back anytime. But if the motor is operational but just the rear cogs slipped off then I doubt it will throw up any codes 

Edited 19 November, 20241 yr by andyz0

Update: no fault codes as expected, so motor itself works but I think a connecting cog or whatever to the rear flap is broken. 
I took it in for its mot at ŠKODA and got them to look at it, they concur about what the problem is, but reckon the dash needs to come out just to get to the motor (not cheap). Is that the case? Has anyone fitted a replacement motor? Location does look pretty inaccessible.