[RatedEM]

I just picked up my convertible n54 not too long ago, and to say the least I'm in love with this car. My only issue is... the AC is blowing hot air out; I'm thinking it needs a recharge. Since the car was rarely driven by its old owners and sat in the garage all day I think the refrigerant leaked. just wanted a second opinion and see what you guys thought! Thanks.

[Needbmwpartzz]

Check your vent switch to make sure they are all set on the blue side....may be the issue

[RatedEM]

Originally Posted by Needbmwpartzz

Check your vent switch to make sure they are all set on the blue side....may be the issue

It's set on the blue side, I played with every little thing trying to get it to blow cold air. Used the auto button, the snow flake, even max AC.

[hernacec]

Go ahead and by an AC PRO with the gauge and charge it back up, literally takes a couple minutes to do and will fix your problem.

[RatedEM]

Originally Posted by hernacec

Go ahead and by an AC PRO with the gauge and charge it back up, literally takes a couple minutes to do and will fix your problem.

Yep I went ahead and did that yesterday.... Problem solved! Thanks guys!

[Velocity26]

I want to throw this out there for anyone charging the A/C themselves. I knew that my system was not working up to it's potential and tried to add some Freon using the cheap auto parts single(suction) gauge recharge kits.

On my car, regardless of how much freon I added, I could not get the suction pressure even close to where the tables show that it should be for the temperature that I was charging it at. I ended up hooking up some professional gauges and I had overcharged the system according to the high pressure side, while the low pressure side was still showing low. I consulted with a friend (licensed A/C tech) and he told me that the tables are designed for fixed orifice systems and many newer systems use a temperature compensated variable orifice (like a wastegate) to manage the pressures and keep optimum performance in all conditions.

He told me to adjust the charge to get the high pressure side within spec's and ignore what the low pressure side said, and see how that works. I followed his advice and the A/C was soon blowing out 38 degree air and cooling perfectly. The suction pressure is barely showing any higher (2-3 lbs) than before charging, although I added nearly a full (large) can of Freon.

TLDR version, you cannot rely on the auto parts single gauge kits to get the pressures right on your 335i, at least not on mine.

[BRD1234]

Originally Posted by RatedEM

I just picked up my convertible n54 not too long ago, and to say the least I'm in love with this car. My only issue is... the AC is blowing hot air out; I'm thinking it needs a recharge. Since the car was rarely driven by its old owners and sat in the garage all day I think the refrigerant leaked. just wanted a second opinion and see what you guys thought! Thanks.

I had my AC blowing super hot not too long ago. It would blow hot when sitting in traffic but when moving it would be slightly colder (by slightly colder it would go from blowing 89 degrees to 69). Living in Miami it was terrible for me to drive my car. Took it to a shop and he said my compressor was shot so I purchased a new compressor and did it myself and now my AC is blowing 46 degrees.

[RatedEM]

Originally Posted by BRD1234

I had my AC blowing super hot not too long ago. It would blow hot when sitting in traffic but when moving it would be slightly colder (by slightly colder it would go from blowing 89 degrees to 69). Living in Miami it was terrible for me to drive my car. Took it to a shop and he said my compressor was shot so I purchased a new compressor and did it myself and now my AC is blowing 46 degrees.

I ended up just recharging the system using a can of R134A, works like a charm, haven't run into any issues since! Glad you got your issue resolved!