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Discussion Starter #1
Hey guys

I own 2002 156 2.0 TS and about month ago weird things happens. When its very hot outside (above 30C) when I start air con compressor kicking on/off all the time. When outside temp goes down (evening9 everything is back to normal. Tried re-gas, 1st time we put 650g because its pre-facelift model, 2nd time we put 500g but its always same problem. There is no leaks in system. What can I check next?

Sorry if I asked again the same question that someone ask, didn't find anything and sorry for my English I'm from Croatia.

Cheers!
 

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Have you checked or tried to replace the pressure sensor?
The pressure sensor will cut the power to the electric clutch for the compressor if the pressure is too low or too high.
 

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Discussion Starter #3
The one on high pressure pipe? I was thinking of it but weird thing is it only happens when car is parked on sun, when it's parked in the dark then it works great.

And one thing more. Pre-facelift 2002 is it 650g or 500g gas? When it works it works great even with 500g.

Going to try pressure sensor on monday.

Thanks
 

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If recall correct it should be 650g on a pre-facelift.
The presure in the AirCon system will also be influenced by the ambient temperature.
 

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I have a similar issue and suspect the condenser to be ripe for replacement. Took the bumper off, cleaned it best I could and it has improved things, but not significantly. When AC is on, the fan runs at high speed almost constantly.
 

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Discussion Starter #6
I cleaned my few days ago with high pressure washer but its the same. Gonna try tomorrow pressure switch and now i'm thinking that maybe its the AirCon relay? If its broken maybe he shuts AirCon on/off.
 

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Discussion Starter #7
I cleaned my few days ago with high pressure washer but its the same. Gonna try tomorrow pressure switch and now i'm thinking that maybe its the AirCon relay? If its broken maybe he shuts AirCon on/off.
When its working fan starts normally and on open road he slows down, but when it goes crazy fan can't start at all
 

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If I understand correctly, your fan doesn't work when it's hot, so the compressor keeps turning off as there's too much pressure. I'd avoid (trying) using it at all until you find the problem.

Make sure the fan works properly, you can use MultiEcuScan to test both low and hi speed.
If low speed doesn't work, check the fan resistor (they're known to fail).
If the fan doesn't spin at all it's most likely a connection issue, trace and check the power wiring and connector to the fan.
 

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Discussion Starter #10
Okay i will, but if its resistor or a fan itself then he wouldn't start at all(I think) and every afternoon and evening he works perfectly and engine temp is normal. Hi speed works cause it turns on in traffic when temp gets around 95C
 

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Discussion Starter #11
Both fan speed tested and both works, pressure sensor replaced and problem stayed. Gonna try to clean interior temp sensor.

Any idea guys cause its insane drive the car which stayed 10h on sun ?
 

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Just a thought...
When regassing and changing components have you thoroughly vacced the system out before adding fresh refrigerant?
If not any trapped air in the system will be non-condensable and lead to a rise in head pressure.
You really need to do this properly with a vacuum pump and proper gauges, just purging the new gas through is not a reliable charging method on cars with such small gas charges.
 

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Discussion Starter #14
Yeah, everything is done in service with new equipment and vac for 10 minutes. We made a leak test and pressure is standing still. Funny thing is that until today nobody belived me cause when car is service it works good because of cooler temp inside and after being outside in sun again same problem(last 5 days between 33C and 36C)
Thinkig of something that can lose connection when hot or I have to use a hammer :)
 
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