AC/heater temperature control

1991 OLDSMOBILE NINETY-EIGHT REGENCY
204,000 MILES • 3.8L • 6 CYL • FWD • AUTOMATIC
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JOHN D. HACKWORTH
  • MEMBER
  • 1 POST
Entire AC system recently rebuilt and works fine when it works.
I set the temperature at sixty degrees and turn the AC on.
Sometimes it blows cold and some times it does not.
It is very hot now, near one hundred degrees, in the St. Louis, MO area and the system will not blow cold.
I have been told my "HVAC controller" under the dashboard needs to be replaced? Is this correct?
Jul 11, 2017 at 12:23 PM
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HMAC300
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 48,601 POSTS
See picture on how to run a self diagnostic on it. Then if any codes get back to us. it can be a sensor or anything messing it up. It can also be controller unless it is a vacuum problem.
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Jul 11, 2017 at 12:46 PM
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