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Discussion Starter · #1 ·
If its not one thing its another, now the A/C isnt cold. I checked the servicing with a DIY Freon kit, its right in the middle of the green. The compressor clicks on and off. I tried pulling the #18 and 27 fuses as mentioned in other A/C threads to set the actuators.
I get balanced airflow, I have no codes. the outside air temp reads correct, I thought maybe that sensor may be an issue.

With no codes I dont know what to do next. We havent hit 100 here yet but 90s is still hot enough
 

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need to know outlet air temp, also those "do it yourself freon kits" are crap- they cannot put a good charge in the system for the following reasons: they do not pull a vaccum on the system to remove all non-condensable gasses, they do not pull a vaccum to allow a full charge, and you run a high risk of contaminating your refrigerant charge with the wrong refrigerant.

2 of the biggest things you need to know when diagnosing A/C issues are outlet air temperature, and system pressure- high side and low side.
 

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Discussion Starter · #3 ·
I found a better diagnosis. THe car is stuck in Defog. No matter which vent I switch to it wont switch out of defog air flow. The digital display shows its switched but the air constantly comes out the top of the dash.
So when I get home today I get to look into that, either the vaccum line is disconnected or the actuator has gone bad.
Atleast it will be a cheap fix, just time consuming getting the dash apart.
 

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I am experiencing the same systems you have Alini, however, my system does blow through the correct vents. Luckily, I have a scan tool and after looking at all the numbers and running a diagnostic check, it looks like my HVAC head unit may be bad, although it is more likely to be the actuators as they are the more common failure. I lucked out twice because I have a extra HVAC unit sitting around. :D
 

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Discussion Starter · #5 ·
I am hoping its just the vaccuum line come off the manifold, thats no cost to repair but with all the issues I have had so far I expect to have to change everything in the system.:smack
 

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I am hoping its just the vaccuum line come off the manifold, thats no cost to repair but with all the issues I have had so far I expect to have to change everything in the system.:smack
Which vacuum line are you talking about?
 

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Discussion Starter · #7 ·
The main door actuator is vaccuum driven per the service manual. The electric actuators are for the dual zone doors which are different. The lin plugs in the back of the intake manifold if I recall correctly, have to check the book once I get home
 

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The main door actuator is vaccuum driven per the service manual. The electric actuators are for the dual zone doors which are different. The lin plugs in the back of the intake manifold if I recall correctly, have to check the book once I get home
Ah yes, you're talking about the little black vacuum line to the left in this picture:



The only thing is if that hose is unplugged, you'll know it from all the hissing you will hear. It is very obvious.
 

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Discussion Starter · #9 ·
There is another smaller one back there too, I dont want to have to remove the intake again but we will see.
 

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The other one is a drain, not a vacuum line. The one in that picture is the only one that goes to the HVAC.
 

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Discussion Starter · #11 ·
The other one is a drain, not a vacuum line. The one in that picture is the only one that goes to the HVAC.
The one in your pic is brake booster isnt it?? Like I said til I get home and check the service manual I am not 100% on the location but it is a vacuum actuated I read that last night
 

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Discussion Starter · #12 ·
I got this pic from your oil pressure sending unit thread, it says the one small line is for HVAC, Im afraid thats the one thats fallen off.

 

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That's the one I'm talking about. It will hiss like a alley cat so you'll definitely know that it is unplugged as soon as you start the car. Ask anyone who has forgot to plug it back in. There was a thread not to long ago where somebody put their manifold back on, started the car and then... hssssssssssssssssss!

I was like yep, you forgot to reconnect that hose! :thud:

You should have seen this picture too.

 

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Discussion Starter · #14 ·
Ive never heard a wooshing noise and I just used an inspection mirror and confirmed the hose is connected (good and bad news)

Good news, I dont have to mess with trying to get in there to connect it.
bad news, Whats really wrong with the car?? So next week its off to the dealer for some T/S help. Air out of the top of the dash is cold, just need to get it out of the main vents so I dont crack a windshield.
 

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Yours may be a head issue also but you need a scan tool so that you can command the doors open and closed. That's what is going to pinpoint your problem.
 

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Discussion Starter · #16 ·
The book calls for just a DMM, and check for voltage at specific pins. I may be able to just do this myself.

The fun part, it says to disconnect the vacuum/electric solenoid....which is not listed anywhere in the book except one wiring diagram. So I guess I tear into the dash and find it. 6 wires and 6 vacuum lines going to it, cant be hard to identify. Just dont know how far I need to rip it apart to find it
 

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I found that the vacuum supply line for my hvac had been cut and repaired where it passed through the firewall with the wire loom. I found this out while running some wiring for my nitrous system. I don't know if yours could be cut in the same spot but it can be easily inspected from the firewall under the hood once the battery has been removed.:thumbsup:
 

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I sometimes have that problem, what I do is with the A/C on, turn the cabin temp knob all the way to 90, then turn it back down to 60. It sometimes takes 2 or 3 cycles from hot to cold but usually solves the problem. It seems the thing that seperates the hot and cold air coming into the cabin gets stuck and lets some hot air to mix with the cold air and the A/C doesn't seem cold. So making it go back and fourth seems to get it unstuck and solves the problem. I know it doesn't sound very scientific and it may or may not be your problem but worth a shot. Good luck bro!
 
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