Hans W

I´m am a new owner from Sweden of a Lexus LS 400 -96 16200 km.
It is very economical without the aircon running. If I run it the car accelerates & decelerates with the switching on and of of the compressor. If I am braking at low speed and the compressor shuts off ( under thermostatic control) I almost come to a dead stop. She drives like a dream with no air con and like a runaway horse with it on. Does anyone have any advice please?

Any advice and suggestions would be much appreciated

Och

iTrader: (3)

Its absolutely normal. When you turn the compressor off, it increases the engine speed by around 300 RPM, and when you shut it off it decreases it back to normal. Its basically equialent to stepping on the gas and letting go of it. Every car does the same thing, but your car has a V8 with a lot of torque, so you are going to feel the effect of these 300 RPMs moreso than in a car with a smaller engine.

Harky

Have the air control valve checked. It's located on the front of the intake manifold. This valve compensates for the cycling of the A/C and corrects/prevents the power surging. I feel no such surging in my 96 when the A/C commpressor cycles.

Hans W

Ok, thanks for your input. I'll look into what you say, Harky.

Best regards !

Hans W