Is it the AC? funny noise when idling.

Kevmc75 · 29th November 2012, 20:18

Rover 75 CDT

When Idling can here something kick in for a second or two every minute to three minutes.
If you press econ on the in car heater controls it stops.
Im guessing econ is economy, which means it switches off the air con presumably.
Im just wondering is this noise of something kicking is normal really.
Also sometimes when im picking the kids up from school the car could be idling for some time, and the tempreture gauge never moves from half way (optimal) running temp.
But i never here the fan kicking in, only this aircon noise.

FLYER · 29th November 2012, 20:21

Quote:

Originally Posted by Kevmc75

Rover 75 CDT

When Idling can here something kick in for a second or two every minute to three minutes.
If you press econ on the in car heater controls it stops.
Im guessing econ is economy, which means it switches off the air con presumably.
Im just wondering is this noise of something kicking is normal really.
Also sometimes when im picking the kids up from school the car could be idling for some time, and the tempreture gauge never moves from half way (optimal) running temp.
But i never here the fan kicking in, only this aircon noise.

Is it a whoooping sound.

Kevmc75 · 29th November 2012, 20:35

nah not really just like a compressor or fan kicking in...
however the other day when sat there i did hear only once a fast kinda whistle... thought nothing of it at the time mind..

FLYER · 29th November 2012, 20:46

Quote:

Originally Posted by Kevmc75

nah not really just like a compressor or fan kicking in...
however the other day when sat there i did hear only once a fast kinda whistle... thought nothing of it at the time mind..

That whistle was most likely the well known WHALE WHOOP sound from an AIR-CON system requiring a service , ie a recharge .

I had it on my first 2 75s and it indicated a recharge was needed .

Others may be able to add to this.

calibrax · 29th November 2012, 20:50

The noise is the fan is coming on, but at low speed. The low speed operates whenever your aircon is on, which is why you don't hear it when "econ" is lit up.

ProfDave · 29th November 2012, 20:50

sounds just like its the aircon working!

Mike Noc · 29th November 2012, 21:06

Quote:

Originally Posted by Kevmc75

Also sometimes when im picking the kids up from school the car could be idling for some time, and the tempreture gauge never moves from half way (optimal) running temp.
But i never here the fan kicking in, only this aircon noise.

The CDT is a very cool running engine and will happily idle without needing the fan even in warm weather.

Mike

Kevmc75 · 29th November 2012, 22:01

Thanks all...
Yeah when the noise came on i presumed it was the fan, but i opened up the bonnet and looked at the fan it does not move.
Must be the aircon, so im not too worried it seems its as i thought.
perhaps the aircon could do with a service.
I have been reading the thread where BMW replied to one of the guys on here about the stats,it seems that these are just very cool running engines, and in most cases the fan will hardly ever come on...
Dont know if a cool running engine is good bad, but to me it hardly can be bad..
prefer it to cool than hot.
I think they are the best Diesel engines out there, they sound so refined.
I used to own a citroen C5 with the acclaimed Peugoet engine, and i know people who have cars with the same engine in its many guises Ford citroen Peugoet Volvo, and they are noisey and rattly...

SD1too · 29th November 2012, 22:06

Quote:

Originally Posted by Kevmc75

When Idling can here something kick in for a second or two every minute to three minutes.
If you press econ on the in car heater controls it stops.

Kevin,

Check that your engine cooling/air con. condenser fan is working at slow speed as follows:

With a cold engine, turn on the ignition and press 'demist' on the air con. panel. Walk to the front of the car and listen at the radiator grille. Is the fan running?

Simon.

Jules · 30th November 2012, 00:07

Yep sounds like classic case of duff cooling fan (fail anywhere from 50k upwards) and condenser will be passed it's best cooling the gas after 90k miles. (corroded fins)

Also get some PAG 46 compressor oil into the system asap.
Many had insufficient concentration from the factory.

Many owners have renewed the cooling fan but not the condenser which is a real shame.
I can hear all those groaning overheating compressors from here and worst still a new cooling fan will be working overtime after ramping up to high speed because of an inefficient condenser which in turn shortens the life of the motor.

Bit of a viscous circle really, but I carry all the bits you need plus a fitting service.
See links below

29th November 2012, 20:18	#1
Kevmc75 Avid contributor Rover 75 Tourer Cdt Join Date: Nov 2012 Location: Cork Posts: 166 Thanks: 0 Thanked 0 Times in 0 Posts	Is it the AC? funny noise when idling. Rover 75 CDT When Idling can here something kick in for a second or two every minute to three minutes. If you press econ on the in car heater controls it stops. Im guessing econ is economy, which means it switches off the air con presumably. Im just wondering is this noise of something kicking is normal really. Also sometimes when im picking the kids up from school the car could be idling for some time, and the tempreture gauge never moves from half way (optimal) running temp. But i never here the fan kicking in, only this aircon noise.

29th November 2012, 20:50	#5
calibrax Posted a thing or two BMW 4 Series Join Date: Nov 2008 Location: Rochester, Kent Posts: 1,975 Thanks: 29 Thanked 37 Times in 28 Posts	The noise is the fan is coming on, but at low speed. The low speed operates whenever your aircon is on, which is why you don't hear it when "econ" is lit up. __________________ Steve 2004 MG ZT+ CDTi 160 (sadly now gone!) 2015 BMW 435d GranCoupe XDrive

30th November 2012, 00:07	#10
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Yep sounds like classic case of duff cooling fan (fail anywhere from 50k upwards) and condenser will be passed it's best cooling the gas after 90k miles. (corroded fins) Also get some PAG 46 compressor oil into the system asap. Many had insufficient concentration from the factory. Many owners have renewed the cooling fan but not the condenser which is a real shame. I can hear all those groaning overheating compressors from here and worst still a new cooling fan will be working overtime after ramping up to high speed because of an inefficient condenser which in turn shortens the life of the motor. Bit of a viscous circle really, but I carry all the bits you need plus a fitting service. See links below __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

29th November 2012, 20:35	#3
Kevmc75 Avid contributor Rover 75 Tourer Cdt Join Date: Nov 2012 Location: Cork Posts: 166 Thanks: 0 Thanked 0 Times in 0 Posts	nah not really just like a compressor or fan kicking in... however the other day when sat there i did hear only once a fast kinda whistle... thought nothing of it at the time mind..

29th November 2012, 20:50	#6
ProfDave This is my second home ZTT, Contemp Saloon, Duotone Tourer Join Date: May 2012 Location: Llandeilo Posts: 4,192 Thanks: 290 Thanked 387 Times in 333 Posts	sounds just like its the aircon working!

29th November 2012, 22:01	#8
Kevmc75 Avid contributor Rover 75 Tourer Cdt Join Date: Nov 2012 Location: Cork Posts: 166 Thanks: 0 Thanked 0 Times in 0 Posts	Thanks all... Yeah when the noise came on i presumed it was the fan, but i opened up the bonnet and looked at the fan it does not move. Must be the aircon, so im not too worried it seems its as i thought. perhaps the aircon could do with a service. I have been reading the thread where BMW replied to one of the guys on here about the stats,it seems that these are just very cool running engines, and in most cases the fan will hardly ever come on... Dont know if a cool running engine is good bad, but to me it hardly can be bad.. prefer it to cool than hot. I think they are the best Diesel engines out there, they sound so refined. I used to own a citroen C5 with the acclaimed Peugoet engine, and i know people who have cars with the same engine in its many guises Ford citroen Peugoet Volvo, and they are noisey and rattly...