AC Problem

[RielyHodge]

My AC blows cold air when it's on, but when I drive around or leave the car on for a long enough period, it stops blowing cold air and shuts off the light above the AC button. I am hoping that someone knows enough about AC systems to help me out because neither me or my dad has any clue what's wrong with it.

 

[86GT351]

First thing is scan to see if there are any codes. Even without a light in codes might be stored. When the AC goes off you need to check and see if your fan/s are running. Might be a condenser fan issue.

 

[07 Boss]

Do you have a set of manifold gauges you can hook up to the AC? This can help diagnose the issue. I'm kinda thinking it may be a pressure sensor somewhere triggering the shut down. Could be you're a little low on refrigerant. Could be a restriction causing the build up or lack of pressure in the system somewhere. Could be a lot of things but a set of gauges will help you narrow it down.

 

[RielyHodge]

First thing is scan to see if there are any codes. Even without a light in codes might be stored. When the AC goes off you need to check and see if your fan/s are running. Might be a condenser fan issue.

I scanned my codes, I got "C3F33" which seems to be an EGR code, and "P1464" which seems to be an electrical issue involving the AC. I think we've found the problem. I went to check all of my fuses associated with the A/C, and they all look good. It started raining outside, so I came back in, so I didn't get a chance to look at any of the connectors or connections to make sure all of that was good.

 

[RielyHodge]

Do you have a set of manifold gauges you can hook up to the AC? This can help diagnose the issue. I'm kinda thinking it may be a pressure sensor somewhere triggering the shut down. Could be you're a little low on refrigerant. Could be a restriction causing the build up or lack of pressure in the system somewhere. Could be a lot of things but a set of gauges will help you narrow it down.

I do not have manifold gauges. If I went and got some, where would I test the pressure at?

 

[86GT351]

P1464 is probably there because the PCM is asking the compressor to turn on and its not turning on.

 

[RielyHodge]

P1464 is probably there because the PCM is asking the compressor to turn on and its not turning on.

It was on while I was running the test, so basically it works whenever I turn the car on, but when I am driving around long enough or if the car is on long enough, and it's never a consistent time, it will decide to just shut off. The code reader itself said something along the lines of it turning on while running the test, but it was on when the test started, so I don't know.

 

[JC SSP]

Could be evaporator is freezing over… next time it happens turn the A/C off but leave the fan speed on high… then engage the compressor after a few minutes to see if it gets cold again.

 

[RielyHodge]

Could be evaporator is freezing over… next time it happens turn the A/C off but leave the fan speed on high… then engage the compressor after a few minutes to see if it gets cold again.

The problem is that it shuts off the a/c. I believe the fan still blows air, but I can't turn it back on after it does that either. But once the car is turned off and back on the a/c will turn on again.

 

[07 Boss]

I do not have manifold gauges. If I went and got some, where would I test the pressure at?

You hook them up to the high and low pressure ports (passenger side near the wheel well). There you check the static pressure which is used to determine if there is enough refrigerant and then you check it with the system running. You will have to look up the range they should be in when operating properly. When pressures are too low or high or the combination of high and low pressures on each side of the system then can be used to determine if and where a fault in the system is occurring. In your case it looks like everything runs properly and then over the course of time there is a failure of some sort. Normally you should keep the gauges hooked up for a few minutes of running the system but for you I might keep them on there until you have the ac turn off again. This way you can check if there is a slow build of pressure or not and determine if there is an actual problem with the system or if there is some kind of electrical issue.