Weird A/C behaviour

[bear55]

The air from front vent is getting weak after 30ish mins of driving, but the rear remain the same. It also happened if the speed is over 140km/h+, but mostly in high speed not city driving. Turning on off the A/C for a short time it will becomes normal, then it will happen again after, its very annoying to keep pressing the A/C button on and off.

What problem would that be? Any input is appreciated, thanks!

[KurtsM5]

"Auto" on?

[M5_Raz]

Sounds like the AC compressor is giving out. Fairly common but expensive to replace.

[bear55]

Originally Posted by KurtsM5

"Auto" on?

Not auto, but auto also happened

[bear55]

Originally Posted by M5_Raz

Sounds like the AC compressor is giving out. Fairly common but expensive to replace.

The air from all vents are very cool if normal, problem is just wind from the front vents getting weak but still cool, and the rear are very cool also with normal wind, if compressor is faulty, the rear shouldn’t get cool.

[M5Rick]

a/c could need a recharge.

[KurtsM5]

Originally Posted by M5Rick

a/c could need a recharge.

I think what he's saying is the flow from the vents diminishes, not that it blows warm. Sounds like the blower motor is tired.

[M5Rick]

Originally Posted by KurtsM5

I think what he's saying is the flow from the vents diminishes, not that it blows warm. Sounds like the blower motor is tired.

Could be failing battery.
Link
https://www.bimmerfest.com/threads/b...n-high.675322/

Of course this should go to bear55 but in connection with what you said to me.

[bear55]

After some study, I guess it should be the evaporator sensor freezes up like that happened to 3 series. It only happen during highway cruising in hot day, and haven’t seen it happen during stop and go traffic.