Car A/C Fan Speed Help (VY SV8) - next to no air blowing out

[Black_Bug]

Hi,

Late last year (I think) I posted up a thread about our family car's air conditioner not working (turned out to be a leaking compressor).

We now have a new compressor and do have air conditioning, but the fan speed is not at full capacity (if that makes sense). As in the fan cannot blow out air fast enough to make the car comfortable to sit in (with the a/c working).

I have checked the evaporator core as suggested in the DIY section incase it was sludged up, but it looks like new.
Could the mechanism that switches air to the window, floor, etc be not sealing? I can't feel air coming out anywhere other where the switch is set to.

Can anyone tell me what the problem could be, or somewhere to check?

Any help would be really appreciated.

 

[HSV 671]

So you're saying that the position control does not work to where you set it? That sounds like a vacuum leak. It would most likely be under the center dash: a perished/loose/cracked hose or the diaphragm might be crook. Try the one way valve in the engine bay, around the fire wall. It might be faulty. All commodores (from the 80's --->) use vacuum as the vent control.

 

[Black_Bug]

Well the speed increases on each setting but, compared to my parents series 2 vy (v6) it feels like its 1 notch out (if that makes sense). Also, a new problem we have just discovered, started the car to cool down for bubs, and came back and noticed the air stopped all together (it was on high, recycled air, and ac was on). It cut in and out every few seconds for a while after that then came good". I will check out the vacuum side of things as you suggested but it sounds electrical?

Also, when the compressor was replaced they said they checked and pressure tested the system, would that include the vacuum side of things?

 

[Gab vs]

I had a similar problem, I cleaned the blower fan (I think thats what its called? behind the glove box) I was covered with dirt.
I actually found the info from this forum over 1 year ago.
Works excellent now

Sent from my GT-I9305T using Tapatalk

 

[Black_Bug]

Ill have a look it didnt look too bad when I had a peak at the evaporator core (also in the DIY Bit) but will check and clean again. I can hear it trying to push air out but it seems to struggle and surge air on and off

 

[HSV 671]

Your ac relays sounds like they are crook. Replace them all. Sounds like there is too much load on the electrics for the relay to handle. If that is what happened if the fan was cutting in an out.

 

[Black_Bug]

Thanks, I checked the fan and it wasnt too bad but pulled it out and checked everything and cleaned it, it was fairly clean anyway.

Would i just change the a/c relays, or would I do the blower fans, etc. I did notice there were a few that were off colour (brownish tinge) on top but I think that was not the a/c relays.

 

[HSV 671]

Could also be a faulty fan speed resistor. Check your connections also. The Brownish colour on the relays shows heat.

 

[Black_Bug]

So heat affected relays mean the fault is elsewhere? or do they break down over time?

 

[Nut Kracker]

It doesn't necessarily mean there is a fault elsewhere (fairly unlikely). It's probably just that the relay is dying.

They do break down over time and tend to cut off when the relay gets too hot and then come on again when it cools down.
I would be checking the 'Blower Inhibit' relay.
That relay always comes on when the engine is started, regardless if the blower fan is switched on or not.