AC delay before cooling
 

i've

More likely your aux fan is not working. Is the pressure checked with the engine running and the compressor clutch engaged? Don't say that the AC button is on, verify that the compressor clutch is engaged.

With a good compressor you should be getting a low side reading of 35-45 psi. What was the high side reading?

Most likely the compressor had crapped out. When you just replaced the coil for the compressor the smart thing would have been to replace the entire compressor and clutch with either a new or rebuilt unit.

Here's a video on why you should had replaced everything.

https://www.youtube.com/watch?v=YirLz1j-vCY

Have you been adding refrigerant to the system? You could had overcharged the system. I have already posted how to add refrigerant to a system. Go and search on my post fore AC.

Yes any time the system is opened the receiver/drier should be changed. Refrtigerant should be added to an empty system by weight, not by reading on the gauges. If you already have some refrigerant in the system, they should recover the refrigerant and add the refrigerant by weight thereafter. Topping off a system is not the correct way to recharge a system.

It could be the compressor control valve.
I read about it quite a while ago on Bimmerfest under e60's I think it was.
Apparantly, it can be replaced separately to the compressor, but is hard to get to. I believe the compressor has to be removed.
They suggested the valve gets sticky and is slow to respond.

The values you listed are normal:

- Engine off (or AC Off): "Low-side" Pressure should be around 100 psi. This is b/c the compressor is off.

- AC On: the compressor pumps R134a "uphill", so the high side now reads some 200-280 psi, while the low side is 35 psi or so.

Do some more readings before replacing the AC Compressor, as this usually lasts some 200K+.
My compressor is still stock at 120K.

I don't think that is normal

Wisful thinking. Modern compressors uses reed valves. They normally break before they become stuck.

Here's a video on how the inside of a modern compressor looks like and the reed valves.

https://www.youtube.com/watch?v=w3aqgpKz5nI

It may be wishful thinking that icecold32 will help lubricate the valve, But these compressors do use a control valve that gets stuck causing a delay in cooling, so he is on the right track.
AC Delay 528i 2008 - 5Series.net - Forums
Something like this:
Control Valve(for variable displacement A/C compressors) | Products | EAGLE INDUSTRY CO.,LTD.

The later days X5s with the variable displacement compressors uses a control valve, but he has a 2003 BMW which should still use the old compressor.