A/C cut off.
Fleet Mechanic
Joined: Aug 2015
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From: Candy Mountain
The AC cutoff doesn't kick in all that often. Most people would never know it existed.
But a vacuum leak will cause the AC to come out of the defrost vents under moderate engine load like climbing a hill.
But a vacuum leak will cause the AC to come out of the defrost vents under moderate engine load like climbing a hill.
Hotshot
Joined: Jun 2015
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I would question why you are driving around with the gas pedal always mashed to floor? The truck is either down on power because something is wrong or you are overloading the truck.
Senior User
Joined: Feb 2012
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Well, mine must be broke, it never did that. Nor any other vehicle I ever owned. I have had some that would act strange because of vacuum loss at WOT.
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Senior User
Joined: Feb 2012
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Just to test the AC for WOT protection, Unplug the connector at the AC compressor then run a wire from the battery thru a fuse and a switch to the ac compressor, (make sure the AC clutch engages when you turn the test switch on) that will remove any WOT shut down sensor from the AC circuit. Yes, this is a small bit of work, but it will tell if the AC clutch is disengaging.
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New User
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Just to test the AC for WOT protection, Unplug the connector at the AC compressor then run a wire from the battery thru a fuse and a switch to the ac compressor, (make sure the AC clutch engages when you turn the test switch on) that will remove any WOT shut down sensor from the AC circuit. Yes, this is a small bit of work, but it will tell if the AC clutch is disengaging.
Thanks
Hotshot
Joined: Jun 2015
Posts: 12,879
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Relays don’t technically protect anything. That’s what fuses and / or circuit breakers are for.
It’s your truck but I still don’t understand why the compressor temporary shutting off is an issue.
It’s your truck but I still don’t understand why the compressor temporary shutting off is an issue.
Fleet Mechanic
Joined: Aug 2015
Posts: 1,838
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From: Candy Mountain
To actually make an attempt to help you.
Are you actually flooring the throttle when you experience the problem and only when you floor the throttle? Does the AC actually cut out? Are you sure it is not coming out of the defrost vents? Does the fan keep blowing but the air comes out warm?
Are you actually flooring the throttle when you experience the problem and only when you floor the throttle? Does the AC actually cut out? Are you sure it is not coming out of the defrost vents? Does the fan keep blowing but the air comes out warm?
Laughing Gas
Joined: Feb 2015
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Here's what I think is going on, when you rev your motor high it spins the compressor faster, so it's sucking down lower pressure on the low side and if it goes low enough the compressor will be shutoff by a low pressure cutoff switch (if equipped) and it will wait until it sees 35-55 psi to reengage the compressor, this is a safety thing to prevent damage.
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New User
Joined: Mar 2018
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To actually make an attempt to help you.
Are you actually flooring the throttle when you experience the problem and only when you floor the throttle? Does the AC actually cut out? Are you sure it is not coming out of the defrost vents? Does the fan keep blowing but the air comes out warm?
Are you actually flooring the throttle when you experience the problem and only when you floor the throttle? Does the AC actually cut out? Are you sure it is not coming out of the defrost vents? Does the fan keep blowing but the air comes out warm?
Senior User
Joined: Feb 2012
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Mine is a six-cylinder 5 speed with a 3.08 rear end, and I have never had that happen. I think (for all that's worth) you have a vacuum leak, when you throttle up to climb the hill, vacuum drops and the doors that control the airflow are shutting, because there is not vacuum enuff to hold them in position.