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98 GT A/C not working (Read more please)

  • Thread starter Thread starter Chrismac7261
  • Start date Start date Jun 3, 2018
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    100f heat 1998 ford mustang gt ac system help summer
C

Chrismac7261

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Jun 3, 2018
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  • Jun 3, 2018
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In my 98 GT, the ac isn’t working almost at all. I checked the pressure on the low pressure refrigerant pipe, and the pressure keeps fluctuating with the car on. I found that this is happening because the compresser keeps on turning on then off rhythmically in sync with the engine reving higher then lower. Would a recharge fix this or is the ac clutch bad, or is it something worse? My car is a manual if that makes any difference.
 

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  • Jun 4, 2018
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Welcome to Stangnet
On this site there are many how to’s for checking/servicing your AC on your own.
As far as the pressure fluctuating and the Rpm’s raising and lowering when the compressor runs-is normal.
If the compressor is cycling very fast-It’s likely a low charge.
But my best recommendation for you -is to pony up the money to a reputable service shop to evacuate-vacuum and charge your AC system.

If you really want to try it on your own,search for @jrichker s ac how to . It’s written for a fox system,but most of the info translates over.
Hope this helps
 

jrichker

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Chrismac7261 said:
In my 98 GT, the ac isn’t working almost at all. I checked the pressure on the low pressure refrigerant pipe, and the pressure keeps fluctuating with the car on. I found that this is happening because the compresser keeps on turning on then off rhythmically in sync with the engine reving higher then lower. Would a recharge fix this or is the ac clutch bad, or is it something worse? My car is a manual if that makes any difference.
Click to expand...
You have a low refrigerant charge; the low side pressure drops and that causes the compressor to shut off. Add about 12-14 oz of R134 refrigerant and that will probably fix your problem unless there is a leak.
 
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