| A/C cycles cold then warm, then cold again [message #92912] |
Thu, 22 July 2010 20:49  |
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RF_Burns
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
Karma:
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Senior Member |
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My A/C blows cold, then warm then back to cold again.
At first I thought it would go cold when then engine was under more load, going up a hill etc, and there was a vacuum switch cutting off the compressor so save engine HP. But I looked at the wiring diagrams and I don't see such a switch.
I also noticed the longer the drive the duty cycle of cold air seem to decrease to the point were it wasn't really blowing any cold air to speak of.
Am I low on A/C charge? My experience has been when a leak develops it just doesn't deliver any cold. It has always been like this since I have had it, 3 summer now, so I don't think I have a leaky system.
This is the first trip I've had during warm weather where I haven't had a major malfunction so I'm getting down to the little things now.
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
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