Noisy Peugeot 406 Aircon Compressor - Wully Bully
I've got a diesel 406 HDI, 2000cc, Y reg, 170,000 miles, that my wife drives during the week while I use a van for work. About three months ago I heard a loud `clicking' from the engine that we isolated to when the air con was engaged. I took the car to the guy that does our MOT's, his advice was that we needed a new compressor "run it till it breaks properly(!) then replace it". We have run the car for a bit longer without the aircon switched on (it always seemed to default to on when we switched on the ignition, and then we had to switch it off), but now we have the noise continuously, air con on or off. Does anybody know what the noise is, and what is the easiest (and cheapest) way to fix it? I was hoping that it was the electric clutch on the drive pulley and could be replaced, but the MOT guy says it's comming from inside the compressor
Noisy Peugeot 406 Aircon Compressor - Dave N
If it's noisy when engaged, then it's the compressor. Assuming you have checked the other items on the belt run.

If it is the compressor, then it may be breaking up, in which case you may also need an expansion valve, drier (part of the condensor) and a full flush.
Noisy Peugeot 406 Aircon Compressor - Wully Bully
Thanks for that. I haven't checked close up myself, but i did get my wife to take it back to the guys who do the servicing to have another look to confirm where the noise was comming from (inside the compressor, the drive or elsewhere on the belt run), and they said it was inside. the thing is, it's now noisey when the air con is not engaged (light on on the display). Anyway, I'll check myself, thanks again.
Noisy Peugeot 406 Aircon Compressor - Ruperts Trooper
If it's the compressor itself, the noise will stop when air-con is switched off. The only thing moving is the belt-driven part of the clutch.

If the noise is in the clutch or it's bearing, it will be there all the time.

It's a bit academic as air-con clutches aren't generally available as separate components or assemblies.
Noisy Peugeot 406 Aircon Compressor - RichardW
I think I'd be looking at the crank pulley which causes exactly these symptoms - may have been initially that it only did it whilst loaded up with the A/C, but has now deteriorated to where it does it all the time.

Is it illogical? It must be Citroen....
Noisy Peugeot 406 Aircon Compressor - LeePower
Try timing the engine up & locking it off with the timing hole in the bottom pulley, If the bottom timing hole doesnt line up you know the pulley bonding is worn out

Sounds a lot like the harmonic damper is on its way out to me.

Ask Honest John

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