Aircon gone funny

[BimmerDan]

I own a e39 M54 and I recently experienced the following symptoms with the aircon.1. A whizzing noise from the blower which correlates with the acceleration.2. During long distant travel the (100kM-300KM non stop), the air seem to be just cool and not cold; even though bringing the temp. down to 16. The weirdest part is, within city driving its cold even at temp 23. Bizarre...I've briefly checked and there were no leakage of freon. Just want to hear what the experts here can advise on. Thanks

 

[JFT63]

Hi BimmerDan, FYI, am also having prob with my a.cond when it runs on auto mode..at the same temp set like 22 celcius degree, it is just cool in the afternoon but extremely cold in the evening or at nite..the culprit is the outside temp. sensor.. now prefer the manual selection since i could not find any connection to the sensor..hope this helps..cheers

 

[rpmnut]

There could be a number of things causing the problem you described, but when it involves something as complex as the car's HVAC system, I think it's best you leave it to the professionals to sort out, bro

 

[JFT63]

Agree with rpmnut, let someone pro to resolve your problem mate...

 

[BimmerDan]

Thank you to JFT63 & rpmnut for your responses. I'll have the a/c looked at by a pro. Have a great day you two.

 

[jarance]

I own a e39 M54 and I recently experienced the following symptoms with the aircon.

1. A whizzing noise from the blower which correlates with the acceleration.
This could be the sound of the Vanos form the engine compartment.

2. During long distant travel the (100kM-300KM non stop), the air seem to be just cool and not cold; even though bringing the temp. down to 16. The weirdest part is, within city driving its cold even at temp 23. Bizarre...
Cool is correct. The air-con is control by the climate module. It is not control by a thermostat. Hence, it is "just nice" or cool when
during long driving.

 

[BimmerDan]

I own a e39 M54 and I recently experienced the following symptoms with the aircon.

1. A whizzing noise from the blower which correlates with the acceleration.
This could be the sound of the Vanos form the engine compartment.

But the sound does not persist when a/c is off.

2. During long distant travel the (100kM-300KM non stop), the air seem to be just cool and not cold; even though bringing the temp. down to 16. The weirdest part is, within city driving its cold even at temp 23. Bizarre...
Cool is correct. The air-con is control by the climate module. It is not control by a thermostat. Hence, it is "just nice" or cool when
during long driving.

The theory would be applicable if my a/c is on 'Auto' but I've always had it on manual selection and the temp. has always been in a state of comfy cold regardless of distant but never just cool.

However, its good hearing your opinion thanks.

 

[BimmerDan]

The problems with my A/C is solved.


1. A whizzing noise from the blower which correlates with the acceleration.
Its seems the compressor was completely out of oil and therefore making the
whizzing sound. Had the oil put in followed by refilling the freon...problem solved.


2. During long distant travel the (100kM-300KM non stop), the air seem to be just cool and not cold; even though bringing the temp. down to 16. The weirdest part
is, within city driving its cold even at temp 23. Bizarre...
Although there were several possibility that could have caused the AC to behaved in such a manner. I started with the simplest diagnostic which is to check Thermostat. Turns out the Thermostat was dirty (noticeably corroded) and had it polished with (any) metal polisher and after reinstalling it back into the car the difference was instant. I am just glad it wasn't the more expensive repairs such as climate control, sensors, condenser etc


I hope this will help those who are currently experiencing the similar pattern with their AC.