F150 Air Conditioner


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Old 06-11-05, 02:28 PM
aubreym
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Question F150 Air Conditioner

A/C works great until going up a hill of anything else that loads the motor. When the motor loads the air flow switches from the dash to defrost (windshield). When the load goes away, it switches back to the dash. Sounds like some sort of vacuum problem to me. Any ideas?
 
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Old 06-11-05, 07:52 PM
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Yes, the engine is loosing vacuum under load, probably a leak somewhere. The default position for the vents is defrost for safety.
 
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Old 06-13-05, 12:51 PM
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There is a vacuum check valve plumbed somewhere in your vacuum system that needs to be replaced. When working properly, this check valve will pass air freely in one direction, but only minimally in the reverse direction.
 
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Old 02-27-07, 12:28 PM
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Originally Posted by aubreym
A/C works great until going up a hill of anything else that loads the motor. When the motor loads the air flow switches from the dash to defrost (windshield). When the load goes away, it switches back to the dash. Sounds like some sort of vacuum problem to me. Any ideas?
Sounds like you have a small hole in one of your vacum lines that runs to or from the vacum canistor that sits under the hood on the passengers side next to the fender.
 
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Old 02-27-07, 02:33 PM
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Two year old thread, Guy.
 
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Old 02-27-07, 10:54 PM
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Smart remark removed.
 

Last edited by mattison; 02-28-07 at 04:50 AM.
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Old 02-28-07, 02:14 PM
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Originally Posted by the_tow_guy
Two year old thread, Guy.
Sorry about the dig last night, long day with customers got to me.
Peace.
 
 

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