93 St Aircon Clutch Engaging Intermittently

[whiffin]

I have a 93 ST170. The air con went warm so I got it filled. As I left garage (owned by mate) it wasn't working. They assumed leaking and checked, no leaks. They tried the next day, working.

Turns out the clutch on air con compressor engages, but disengages sometimes for no obvious reason. When I was talking to mechanic it 'clicked' off, air con stopped, then it 'clicked on', by itself. I could hear it.

My car isn't climate controlled

They say best to source reconditioned compressor as prob not serviceable, but to ask online

1. Any ideas of why it would do it, and is it fixable?

2. If I need to buy one, where from & how much?

Thanks guys

[btmaldon]

Could be the low pressure switch. If its not sensing correcdtly and thinks the pressure is too low it could be switching off to protect the compressor.

[stef123]

the aircon compressor will engage and disengage, are you still getting cold air all the time though

[whiffin]

Sorry for late replies, I didn't get notifications :(

Btmaldon - where do I find this switch/sensor? You had this before?

Stef123 - no when it clicks off the cold air goes back to air temperature just like the air con is off. It's not "chilled"

I could order refurb or 2nd hand compressor but need to be 100% really

Thx for help. I'll check forum more frequent,ly now I know notifications not working

Cheers

[btmaldon]

The low pressure switch is on the low pressure pipe which you use to top up the air con gas. You should have two pipes with a screw cap on the end covering a pressure valve somewhere in the engine bay. The smaller of the two is the low pressure pipe.

[whiffin]

Cool thanks. Is it easy to replace and/or test?

Could I bypass or something (for testing purposes)?

Do you know of an instance where this has failed and given issues like I'm experiencing?

Sorry for all the questions and thanks for your help :)

[pragmatix]

Its a fairly common fault on lots of cars, not had it myself but have had the high pressure side fail, on my mondeo

[whiffin]

Ah nice one. Thanks mate!