Ac blowing through defrost
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Joined: Sep 2021
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Ac blowing through defrost
So pulled out of the driveway today and when I have my foot on the gas pedal it blows through the defrost when I help off and coast for a minute it comes back to the vents. Is this a vacuum leak and wear do I start looking.
More Turbo
Joined: May 2015
Posts: 633
Likes: 142
From: Staten Island, NY
The 4x4 solenoid is located on the passenger side fender just behind the battery, it cracks underneath and can cause the ac to default to the defroster. Exactly what happened to mine, 40 bucks later I was back in business. Good luck
Hotshot
Joined: Jan 2004
Posts: 19,762
Likes: 1,079
From: St Louis
ANY vacuum leak in the supply to the HVAC control head can cause this symptom. It's just that the PVH solenoid has become one of the more common failures over the years.
You can disconnect and cap off the solenoid's vacuum supply to isolate it from the rest of the vacuum distribution system to help diagnose.
You can disconnect and cap off the solenoid's vacuum supply to isolate it from the rest of the vacuum distribution system to help diagnose.
Hotshot
Joined: Jan 2004
Posts: 19,762
Likes: 1,079
From: St Louis
Read the HVAC FAQs, see signature. for link.
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