According to shop I ended up taking it to, it was because of too much PAG oil in the system. They evac'd and recharged system again, no more problem.....I did have to pulley, tensioner and belt replaced as well.

Mechanic swapped out compressor, pulled vacuum and recharged. Blowing cold. Still have loud engagement bang at start up.

I'm thinking about swapping out the ac hydraulic tensioner, pulley and belt? Any thoughts?

r,

Gus in Vegas

Had Sin City BMW look at the tensioner, belt and other things that could be moving around when the AC is under load. They determined it was the compressor clutch engaging with a bang when I start the AC. Mentioned if the PAG oil is off in the compressor, it can cause this. I specifically asked about...

Thanks for the reply. I was wondering if I should replace the belt, hydraulic tensioner and pulley before i assume anything wrong with the shop recharge to spec. I did replace all 3 of those in 2014....will definitely have a look at it when the ac is being turned on.

96 328i sedan Air Conditioner has loud bang at startup, then cools very well. My AC wasn't cooling too well so i had a neighborhood shop do a recharge. Afterward recharge, was told low and high pressure gauges looked good, system blew quite cold BUT a very loud bang when I start the AC. I don't even...