Hey I was driving today and went into some major traffic. I mean none of the cars moved at all. Well I noticed my AC get hot out of no where. Is that normal when the car is stopped and you are in traffic? I mean the AC wont blow cold air if I didnt move for a long time, it will just blow out hot air. It kinda freaked me out a lot cause I thought my engine was overheating on me or something but when I looked at the temperature gauge, it was still normal. So I was like WTF! I was in 100+ degrees today, got burnt tool. So have you guys experienced this problem when in traffic? I need to this so if it is not normal I will have to take it back to the shop. Thanks

 

The only time I had this happen the air never got cold again and it turned out that my AC line had been eaten through from rubbing against the intake tube of the supercharger.

--Steve

 

take it to the dealer....maybe your system is leaking on your compressor is going bad. Intermittent AC is a sign of something wrong with the system, it has nothing to do with an engine and overheating.

 

won't it also do that is the fan is not turning on? That happened to me on my 240 and I just had to fix the fan.

 

I had the same problem bro, my compressor died. I took it to the dealer and they replace it for FREE!!!

Good Luck with everything.

-JOsh

P.S
Also the intercoler blocks the AC sensor.

 

The radiator fan also has nothing to do with the AC. There is a sealed blower...probably somewhere on the firewall or inside the dashboard that actually blows the air for the AC.
It also sounds like his fan is on and working, but it's just not blowing cold air....so doesnt sound like a fan prob.

 

This actually happend to me. What gq is saying is right. How it works, since we have a big front mount, which pretty much covers everything. What it's happening the fmic is blocking the ac sensor, by blocking what is doing is the engine heats up, so the compressor instead of throwing cold air is function is to cool down the car. When I took the dealer the put frion(spelling) for it to cool down. It work, but just for a week. I went to the track on a sat afternoon like it was between 99-102 degrees. Therefore, the runs and the heat pretty much killed my compressor. Now is working fine.

Good luck again,

-josh

 

I think it is the FMIC. It is blocking the AC sensor. But if I take it to the dealer, wouldnt they know that I added the TT in and void my warrenty anyways? If they know that I have the turbo, I wouldnt think they will cover anything under the hood.

 

Yeah man, they would now the car is turbo and really u did void your warranty, but some dealers are pretty cool. The dealer I go to I have my car under warranty still. The only thing I have to pay is if the have to do extra labor like a tranny swap, which requieres taking out wastegates and downpipe. Hope this helps if your not to far from GA I could probably talk to my service rep and he could probably help you out... Let me know how it goes and good luck.

-Josh

 

I just noticed where u from dude sorry...

 

The cooling fans have everything to do with the a/c!!! The condenser sits in front of the radiator, in your case between the radiator and IC. The cooling fans have to run to draw air across the condenser, especially in idle and low speed conditions. If the fans do not run the a/c builds up too much pressure on the discharge side of the system. If this happens the compressor has a protective switch (High Pressure Cutoff) to disengage it to keep the compressor from burning up or blowing a line off. This switch is usually set around 400-425 psi. If the fans are not working it will only take 10-20 seconds of compressor run time to reach this pressure. Assuming it is around 90+ degrees outside. If it is cooler than that I would say max compressor run time would be 30 secs. before the compressor will cut out.

There are several things that can cause excessive pressure in the a/c system.

1. system overcharge
2. cooling fans not working
3. trash or debris blocking the airflow (leaves, paper, anything that inhibits airflow. Even in some cases between the radiator and condenser is foam to seal them to keep airflow from flowing around them instead of through them.

The easiest way to check your fan operation is to raise hood, start car and turn a/c on. The fans should start immediately. Also on the 350 is a two speed fan, low and high. I don't know exact pressures but I would say that if the discharge pressure goes above 250-275 then the high speed fan would kick in.

This is just general a/c information. You really should let someone with technical knowledge and some guages check system operating pressures. Try to duplicate the exact conditions when your a/c quit so you can show the dealer. Ambient air temps and humidity have a direct effect on system pressures and those are hard to duplicate. If you can't duplicate them then try to keep a record of when it quits cooling and the conditions (air temp, humidity, idleing or travelling speed) this will all help you get an accurate diagnosis.

Check other a/c problems on the board, there have been more than one documented cases of overcharged systems. R-134A is very, very critical to the system charge amount.

Hope this helps!!!!!! If you have any questions PM me.

Tony

 

I dont have AC malfunction. When I drive it works fine only when I am moving. And if I am in traffic and the cars wont move at all, then it will cut off. So I am thinking it is the condensor. It needs to suck air and the FMIC is blocking it and it will stop cause it is not getting no air in. Thanks for all the help guys I think I found the problem already. I guess thats why Suburus have their IC on the hood so it doesnt get in the way of the AC condensor, am I right? Thanks for all the help guys.

--Tim

 

No, Tony has it right. For the AC to work *at all*, there must be sufficient airflow through the condenser. Since it works when the car is moving, there is sufficient airflow, so the IC isn't stopping the flow.

But, when the car is sitting still in traffic, the electric fans *have* to work to give you airflow, because the car isn't moving to create airflow. If the fans aren't working, or aren't working fast enough, you'll get the symptoms you describe.

So the *first* thing to check is with the car stopped, engine running, AC on, hood open, is if the electric fans are running. If they aren't, there's your problem right there. You'll then need to do electrical troubleshooting to find out why they aren't getting juice. If they're running, but not at high speed, that could indicate a problem with the sensor which shifts them to high speed operation, or with the high speed control relay (burnt contacts, etc).

If the fans are running at high speed, check the compressor clutch to see if it is engaged. (You can have someone cycle the AC on and off while watching the compressor to visually confirm the clutch is working.) If the clutch isn't engaging, you have an AC problem that'll have to be troubleshot by an AC specialist.

If the clutch is engaging when someone switches on the AC for you, but then disengaging again fairly quickly while you still have the AC on, then the problem could be that the fans can't supply enough air through the stack of intercooler, condenser, and radiator. In that case *only* would your theory apply.

In that case, you may be in the market for more powerful fans (steeper blade pitch, or more blades, and/or more powerful electric motors). These exist in your friendly neighborhood junk yard (look for a car with a bigger cooling requirement), though you may have to do some fabrication to mount them.