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Possible to bypass A/C compressor shutting down?


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Welcome to the USMB.

 

The A/C compressor cycling is unfortunately normal.  It can however may be minimized by ensuring the proper refrigerent charge is in the system.  Does the air heat up too much?  Are you using the fresh air or recirculating setting?

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The compressor stops running for two main reasons.

One is because the pressure in the system gets too low.

The other is when the evaporator core gets too cold. The compressor will be shut off to prevent icing of the evaporator. The compressor will cycle much more often due to this if you have the control head set to recirculate, but the air should still be COLD since the air moving across the evaporator core will be pulled from inside the car.

If the compressor is cycling and the air is not cold, the charge is probably too low.

 

On newer vehicles the control module will stop the compressor if the throttle is wide open, or if the steering wheel is turned more than a certain amount when the vehicle is sitting still or moving very slowly. Neither of these will apply if the compressor is cycling while driving at a steady speed.

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On newer vehicles the control module will stop the compressor if the throttle is wide open, or if the steering wheel is turned more than a certain amount when the vehicle is sitting still or moving very slowly. Neither of these will apply if the compressor is cycling while driving at a steady speed.

 

Is the reason the compressor turns off if the wheel is turned past a certain amount due to reducing load on the engine?  I've never heard of it.

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Is the reason the compressor turns off if the wheel is turned past a certain amount due to reducing load on the engine? I've never heard of it.

That is exactly why. Reduce engine load and there-by reduce emissions.

 

It's usually just done with a hydraulic pressure switch on the power steering pressure line.

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That is exactly why. Reduce engine load and there-by reduce emissions.

 

It's usually just done with a hydraulic pressure switch on the power steering pressure line.

 

This also explains the sudden drop in RPM sometimes when I cock the wheel too quickly and/or to it's extreme limits.

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That is exactly why. Reduce engine load and there-by reduce emissions.

 

It's usually just done with a hydraulic pressure switch on the power steering pressure line.

 

I'm all for not polluting the planet, but something like this seems pretty ridiculous.

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I'm all for not polluting the planet, but something like this seems pretty ridiculous.

It is, no doubt. Just another way for manufacturers to claim X% of emissions reduction to help satisfy tighter EPA standards. With the recent push toward electricity, most new (2012+) cars now have electric assist power steering. Most of which actually eliminate the hydraulic component altogether.

There are also electrically driven AC compressors.

 

Fine and dandy until the wires get corroded.

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