A/C blows cold then hot when on the gas
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A/C blows cold then hot when on the gas
So when I bought my car last year the ac was working when i recharged it with the diy home recharge kit and it worked fine for a week. then it went out so i took it to a shop and they said the stems were leaking so we switched those out, a week later the ac wasn't working again. I had so much going on I just left it alone and ignored it for a whole year. well a few days ago i decided to get it fixed and I took it to another shop, they tested it for pressure and leak(dye) and found nothing wrong with the ac system. It's been working fine for the past few days but today for the first time it blew hot, but after a minute it went cold again. I noticed that this would happen when the peg on the temp gauge is at the middle point. Also, when I'm under half throttle acceleration through the gears i notice that the air would stop blowing through all vents and the second i let off the accelerator it would blow through the vents again. I've never experienced this before, could a vacuum line do this? Any input would be greatly appreciated. Thanks.
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The baffles that control the cabin airflow passages are vacuum operated. More throttle = less vacuum = baffles move. You have any symptoms of a vacuum leak?
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Wow, sorry to leave this thread with no response I forgot all about this. Well time to bring this back from the dead lol, I can see what you guys are saying about it kickin out at around 4000 rpm but it still happens under normal driving around 2000 rpm shifts. The free-on will only last about 2 weeks before being completely drained. Took it to 2 shops and they still can't find any leaks. Is there a possibiliity the leak can be somewhere behind the dash?
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Do you know if they did a leak check with the engine cold and hot? The expansion and contraction of materials could cause an opening to leak and then seal up the next. I once had a screw puncturing a line (a present from the factory) which leaked only when the engine was hot.
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Do you know if they did a leak check with the engine cold and hot? The expansion and contraction of materials could cause an opening to leak and then seal up the next. I once had a screw puncturing a line (a present from the factory) which leaked only when the engine was hot.
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I will definetely leave it at a shop I really don't want to dive into the A/C system. Another thing that I want to mention was that I still have that problem with hot air coming out of the vents for the floorboard. My HVAC controls are off and I'll be driving and once i'm on the accelerator i can feel hot air blowing on my feet/floorboards but once I let off it goes away. Could this be a vacuum problem? and Could this also relate to my air conditioning problem?
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subscribed.........mine does the floor board thing. i can feel hot air coming into the car/heating up the cabin. im not sure if it is under acceleration only but i know for sure its when the car is moving, say 30mph+
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Have you checked the check valve for the hvac system? It should be sitting right by the passenger side hood strut - where it mounts by the pcm. Also if I'm not mistaken there is a vacuum canister down by the passenger side fog light. Check the lines with a mityvac or similar to verify everything holds vacuum.
There could be more than one issue going on here...I just had to replace the check valve on my 98 V6 last month.
There could be more than one issue going on here...I just had to replace the check valve on my 98 V6 last month.
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As for the air conditioning I think it's coming from the connection to the firewall, when I shut the car off with the a/c running it hisses for a few seconds