? faulty air compressor

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Sat 14 Jun 2003 19:43
? faulty air compressor - ajsdoc
Servicing my 1998 Mondeo 1.8LX today and noticed a clunk coming from the air compressor (according to my Haynes manual). Every 2 or 3 minutes the unit clunks and the drive wheel stops driving the unit.

I'm not sure whether this is normal - it has probably been doing it for ages and I've only noticed today because I've been giving my car more attention than usual.

All advice appreciated.

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Sat 14 Jun 2003 19:52
? faulty air compressor - Sheepy-by-the-Sea
I presume you mean your air-conditioning compressor?

This is normal - the compressor has a magnetic clutch, so that it only works when it needs to - i.e. until it's at the right temperature.

You shouldn't really notice it when you're in the car - you might spot a temporary drop in engine revs if you're idling, and sometimes when cruising you might feel a slight dragging sensation when the pump cuts in.
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Sun 15 Jun 2003 09:56
? faulty air compressor - ajsdoc
Yes - air conditioning compressor.

Thanks for your reply, should the unit be cycling on and off when the air conditioning is turned off? Mine certainly is.
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Sun 15 Jun 2003 18:50
? faulty air compressor - Dave N
It shouldn't cycle when the a/c is off, except on demist.
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Sun 15 Jun 2003 20:24
? faulty air compressor - ajsdoc
Definitely cycling with air con switch off and not on demist. Is this something that will be a big problem or can I ignore?
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Sun 15 Jun 2003 22:04
? faulty air compressor - Dave N
If you don't mind the compressor running all the time, then don't worry about it. If not, check out the switch.
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Mon 16 Jun 2003 07:45
? faulty air compressor - Sheepy-by-the-Sea
Sorry if the first reply was telling you how to suck eggs - didn't know about the 'off' thing!

As well as the switch there may well be a relay somewhere that could have stuck.

Also - is your car a manual or auto? In some autos there's a relay which cuts out the compressor on kickdown to reduce the load on the engine - unlikely to be that, but worth knowing it could be there.

Leaving the compressor on all the time is OK, though if your car doesn't have full climate control it could start to get a bit on the chilly side.
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Mon 16 Jun 2003 14:11
? faulty air compressor - jc
The manual will cut the a/c if you accelerate at wide open throttle and then cut back in again;don't understand your comment on chilly car with a/c on-even Ford suggest using heater and a/c-it just gives hot dry air.
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Mon 16 Jun 2003 17:07
? faulty air compressor - Sheepy-by-the-Sea
Ignorance on my part - only ever had climate control!
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