A/C compressor cycles on and off every 3-4 seconds

1997 MERCURY MYSTIQUE
124 MILES
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CSGMAIL1
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A/C got warmer and warmer last year. Winter was near...didn't worry about it. Summer came...got worried about it. Added E-Z Chill R134a as instructed on can. Compressor started but goes on and off every few seconds. Burning up in Milwaukee....please help. Thanks.
Jul 8, 2013 at 4:14 PM
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SEANGRANT00
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This could be a couple of things.

You could have overcharged the system. What pressure were you seeing after you added the R134?

This would cause the compressor to kick on and then off shortly afterwards..

Let me know


Sean
Jul 8, 2013 at 4:53 PM
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CSGMAIL1
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Instructions on can said pressure should be between 45 to 55 lbs. when the ambient tempature was 85.
Jul 8, 2013 at 6:01 PM
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SEANGRANT00
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What size can did you add to the system? Did you purge any of the air before hand or use a vacuum to recover the refrigerant before?

The system should be around 28-30 with the compressor engaged, and 40 to 45 after it cycles off.


This also could be a couple other things, try this. Apply throttle to about 1500 rpm's and see if the clutch stays engaged.

Sean
Jul 8, 2013 at 6:24 PM
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CSGMAIL1
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I did not purge the system. I just assumed it was low and added. The can is 18 oz. but very little went in before I reached pressure. Tried raising the rpm, doesn't matter. Compressor just keeps kicking on and right back off after a few seconds.
Jul 10, 2013 at 12:41 PM
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CSGMAIL1
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Related question: How do I purge the system to just start fresh? Any help appreciated.
Jul 10, 2013 at 1:23 PM