air conditioning and fuel economy

[brad360]

Does anyone else find their aircon increases fuel consumption quite a lot? I'm thinking maybe 20%. I know mine feels like a trailerload of bricks has just been attached when I turn the aircon on, it noticeably reduces performance. it is not the original compressor. It does work reasonably well, but not a lot of help at 35 deg.

[redline]

there is a very strong belief that aircon affects the cars performance and economy , especially under 2.0 litre engine size which all 300's are .
iirc its because of the extra load caused by the belt when the aircon is in use (i.e. the compressor is being driven ) , it causes more drag and therefore reduces power or rather makes the engine work harder to produce the power .

my mate hired a ford lynx in the states (like the escort over here ) it was a 1.6 and everytime he put the aircon on he had to drop a gear to maintain his speed.

had a quick look on the net

it appears its not just under 2.0 litre
this is from the LEXUS forum so you are in good company

Doesn anyone else with a MKI GS300 notice a performance hit when using the aircon ??

I've had it on and off for the last couple of weeks.

Even at speed around 70mph, if i turn it on and off i'm sure i can feel it...

Could this be a problem ??

[foggyjames]

I know the 360 system disengages the compressor at wide open throttle...so there's one easy solution to the efficiency problem - it's only inefficient if you're using lots of fuel to go slowly

cheers

James