AC sux! not broken, just sux!

[toast_mcmann]

I have a 95 325is, and I live in Phoenix. Man does my AC suck, as a matter of fact all the e36’s I’ve rode in have crappy AC’s. This last weekend I recharged my freon and it didn’t help at all. On full blast the fan still seems a little weak, so I plan on changing my cabin microfilter. Still, I expect my AC will suck. The AC does indeed work, but it just doesn’t compare to other makes AC’s. At this point I want to know if anybody has upgraded their AC, as opposed to merely trying to fix it. I’m sure in some states these stock e36 AC’s cut it but NOT IN PHOENIX, HELP!

[Wayne at Pelican Parts]

I feel your pain. I have 3 E36s. One has no working AC, the 2nd has AC I would rank as good, and the third is the coldest car I've ever owned - ice cold AC. This one is actually a 1995 as well, and I have a pic from my new book to prove that it works really, really well:



Yes, that's 34 degrees F. The bottomline is that the system *can* be made to work very well. Can you tell us more about what you've done to this point, or what your system pressures are?

-Wayne

[toast_mcmann]

wow, wayne! What did you do to get your ac so cold? I'm not exactly sure what is meant by system pressures? When I recharged the system the gauge on the recharger would stay in the lower to upper "normal" range. I say normal because there were no numbers or units of measurement on this strange gauge. Also about 4 years ago I was in a traffic jam and the AC just cut out completely (fan stopped) on me. Since I was broke at the time my mom paid for the repairs, which I unfortunatly can not recall completely. I'm not sure but I thought I remember them replacing the compressor.

[Wayne at Pelican Parts]

My '93 doesn't work as well as the '95. Cowboy is right - you need to evaquate the system to remove impurities, water vapor, etc. and then refill to gain the most efficiency. That 34 degrees is a true reading, but, the photo was taken at night when the ambient air wasn't super-hot (probably about 70 degrees or so). Still, the AC system was shutting itself on and off to prevent the evap from freezing itself (at 32 degrees), so in theory, it could have gotten colder...

-Wayne

[storm31707]

it does really help..Mine works great after I changed microfilter however I have a idle when I turn on my AC. It works well but is there anyway eliminate the idle???? I have a euro pulleys on... is it because of the pulley??? I don't think it's because of that, and I have a problem with muffler, which is not attached to the car.

[Wayne at Pelican Parts]

Originally posted by storm31707
it does really help..Mine works great after I changed microfilter however I have a idle when I turn on my AC. It works well but is there anyway eliminate the idle???? I have a euro pulleys on... is it because of the pulley??? I don't think it's because of that, and I have a problem with muffler, which is not attached to the car.

Which car do you have? Does it have the dual-mass flywheel in there?

-Wayne

[toast_mcmann]

My idle also jumps around when I turn the air on. Whats the deal with that?

[Wayne at Pelican Parts]

The A/C system does place a pretty significant load on the system when it's turned on. It's not uncommon or even abnormal for the idle / engine to shake when the system is turned on. Is this what you're referring to?

-Wayne

[storm31707]

ok that was quick reply!! thanks... anyway i drive 98 M3 and I only got 71K. I had same problem as the other writer, who put up about microfilter. Now my ac is nice and cool, but it idles a lot.

[BMWCowboy]

idle automatically goes up when you turn on A/C->>also shuts off (compressor)when go full throttle

[Wayne at Pelican Parts]

Originally posted by storm31707
but it idles a lot.

I'm not sure what that means exactly? Cowboy is right - the engine will adjust itself slightly when the A/C compressor is turned on and off...

-Wayne

[toast_mcmann]

what I'm talking about is the idle not staying constant. When the a/c is on and I'm just idleing, the tach needle goes up a bit and down a bit. Is that normal? Further more if i'm just siting with the engine running with the a/c on for about 20 minutes or so my car will start to over heat, and as soon as i turn the a/c off or start moving my engine temp returns to normal. Whats up with that? My coolant system is intact and has the correct amount of coolant. Just like my a/c.

[Wayne at Pelican Parts]

Hmm, I can't say I've left the car running on a hot AZ day for 20 minutes. However, the AC system basically takes hot air out of the inside of the car and puts it into the front evaporator, which needs to be cooled by moving air. This evaporator is located right next to the radiator. So, if there isn't a flow of air coming across both the radiator and the evaporator, it's conceivable that the evaporator will heat up the radiator and cause the car to run hotter. I assume your fan is running at that time as well?

How is the car running normally? No overheating issues? A weak cooling system may only show it's weaknesses in the face of really hot temperatures, or idling as in your case. Let's suppose that the thermostat is stuck so that it only opens partially. In normal operation, there is no problem, but when the car is running in hot weather or in traffic, it becomes a problem. I had this exact same problem on my truck a few years ago. Bottomline, if you think the cooling system is not performing up to par, I would:

1- rebleed the system 2-3 times
2- replace the thermostat

-Wayne