A/C stressing engine and heating cabin

Hello everyone ,

I own a 95' 525i with around 140k miles on it. My bmw was previously owned by a yuppie residing in beverly hills. All his woe's with the car he didnt deal with himself but instead took to his local mercedes mechanic. I've been rudely awakened that everything on my bmw has been there since 95'. What I mean to say is, that regular maintenance like oil changes and brake pads etc have not been serviced.
Today was one of the first "summer" days in Los Angeles , it must've been at least 90 degrees and as a result I was using my A/C. I encountered the following problems:
1) When using the A/C , the engine loses a significant amount of power. acceleration is lagged severly. is this normal?
2) The air that comes through my vents isnt very cold and i would expect it to be colder. the air that comes through seems to be choked or clogged. is this normal?
3) The large vent located on the drivers side adjacent to the brake and acceleration pedals expells heat when the A/C is turned on the more i accelerate the more intense the heat expelled grows. as well as over the instrument cluster near the location of the small speaker on the drivers side. around this area there is also a considerable amount of heat expelled.
4) And finally in general even when i'm not using my A/C on fairly cold or lukewarm days the cabin becomes stuffy. I had the same issue w/ my Pugeot, all the heat of the engine exits into the cabin.

Any suggestions or advice on amending these issues would be greatly appreciated.
thanks for your time guys and gals.

it almost certainly needs a cabin filter which will improve smell and air flow a ton, and probably has a stuck heater valve, you can sometimes get the heater valve going again by wacking it while car is powered up and the heat is off, the valves fail in the full heat position

Quote:

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Originally Posted by hoodsstalker

Hello everyone ,

I own a 95' 525i with around 140k miles on it. My bmw was previously owned by a yuppie residing in beverly hills. All his woe's with the car he didnt deal with himself but instead took to his local mercedes mechanic. I've been rudely awakened that everything on my bmw has been there since 95'. What I mean to say is, that regular maintenance like oil changes and brake pads etc have not been serviced.
Today was one of the first "summer" days in Los Angeles , it must've been at least 90 degrees and as a result I was using my A/C. I encountered the following problems:
1) When using the A/C , the engine loses a significant amount of power. acceleration is lagged severly. is this normal?
2) The air that comes through my vents isnt very cold and i would expect it to be colder. the air that comes through seems to be choked or clogged. is this normal?
3) The large vent located on the drivers side adjacent to the brake and acceleration pedals expells heat when the A/C is turned on the more i accelerate the more intense the heat expelled grows. as well as over the instrument cluster near the location of the small speaker on the drivers side. around this area there is also a considerable amount of heat expelled.
4) And finally in general even when i'm not using my A/C on fairly cold or lukewarm days the cabin becomes stuffy. I had the same issue w/ my Pugeot, all the heat of the engine exits into the cabin.

Any suggestions or advice on amending these issues would be greatly appreciated.
thanks for your time guys and gals.

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1) AC will effect the power and it will be noticable (15%?) Sounds like you have more.

2) There is an electric (aux) fan in front of the condensor - it may not be working and would effect the efficiency of your AC system especially at idle and slow speeds. Mine was rusted and had to be replaced but you may get lucky and find it is just a fuse or resistor. Assuming your compressor is actually coming on (and the system is charged), this would be something to check.

3/4) There is also heater control module that may be stuck and forcing water through the heater core at all times which leads to the warmer than expected air in the cabin. If the coolant wasn't changed regularly, it may be rusted/jammed... I got mine for about $100 from Autohaus Arizona.

Also, there is a cabin filter (to the left of the passenger on a US car) that probably has never been changed based upon your comments regarding the prior owner and would effect total airflow once you look at the above issue.

I would suggest tracking down the heat source first and then work the cooling issues - you might want to hold off on running the AC until you get it fixed in case you are running really high system pressures (due to Aux fan) and heating of AC evaporator.

Hopefully some of the experts will chime in and correct me if I have missed anything (and I am sure I have)

Scott

These responses are greatly appreciated , and i will begin my investigation.