A/C starts to go from cold air to warm air as I accelerate

37,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
Avatar
SCHIRICO
  • MEMBER
  • 5 POSTS
A/C works fine at idle and below 25 mph. When I go faster it starts to blow warm air. it is a digital unit on max cold.
Sep 12, 2018 at 7:47 AM
Advertisement
Avatar
ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good afternoon.

Do you have a set of gauges to check the high and low pressures while the AC is running?

Make sure the fans are working on the radiator. If there is not enough air flow, this could cause this issue.

Is the engine running hot? If it is, it will effect the AC operation.

Roy

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak
Sep 12, 2018 at 8:12 AM
Avatar
STEVE W.
  • ✓Experienced Mechanic
  • 15,403 POSTS
Another item to check would be the vacuum lines, The 88 uses vacuum to control most of the actual doors and the symptoms you have sound like a loss of vacuum to the system as the throttle opens up and allows the air door to open and let ambient air pass.
Sep 12, 2018 at 2:47 PM
Add a reply
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.

Frequently Asked Problems for This Vehicle