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AC trouble

Featured Replies

91 loyale AC starts then stops after a few seconds, hitting off then on every time it stops does start to blow cold.

Any ideas why the compressor stops?

could have a refrigerant leak.. the low pressure or high pressure switches could be breaking the circuit.. or even an overcharge if you recently had it serviced..

 

I just can't recommend servicing it yourself.. to much of the a/c system requires special equipment to properly diagnose and repair

 

For a visual check i would follow the lines on both sides of the engine compartment and at the front condensor. Look and run your hands along them looking and feeling for oil residue especially around fittings and valves.

 

 

rllywgn

This may be a bit of a long shot, but here goes...My '91 Loyale needed a recharge and had already been converted to R134. I charged it up and found that the compressor would run fine for a while, then start to squeal, and then stop completely. Turning the AC system off and back on at the dash would get it restarted. I began to fear that the compressor was suffering from lack of lubrication and that it was locking up (thus the squealing). It turned out to be a simple fix: the belt was not tight enough. I re-tensioned the belt and the occasional squealing/stopping thing did not re-occur. My Loyale is now consistently blowing 38 degree air on an 85 degree day (47 degrees below ambient with R134 - I'll take that any day!). Anyway, hope this might help. Good luck!

- Ian

also make sure the pulse coil thingy that hangs in front of the compressor pulley is installed, plugged in, and somewhat lined up parallel to the plain described by the motion of the face of the pulley..

 

I'm not *entirely* certain what exactly it does, but I know the compressor needs to see the proper signal from that thing to turn on and stay on.

also make sure the pulse coil thingy that hangs in front of the compressor pulley is installed, plugged in, and somewhat lined up parallel to the plain described by the motion of the face of the pulley..

 

I'm not *entirely* certain what exactly it does, but I know the compressor needs to see the proper signal from that thing to turn on and stay on.

 

Daeron is spot-on about checking the pulser. I think the reason my compressor clutch was disengaging as the belt slipped is because the slippage caused the compressor to turn slower than engine RPMs, thus signalling clutch disengagement. The pulser measures compressor RPMs somehow and (I assume) the ECU compares engine RPM values to compressor RPM values, and if the two are too far out of synch, voltage is stopped at the clutch. Supposedly this is to protect the belt from breakage if the compressor locks up? In any case, as Daeron indicated, a pulser too far from, too close to, or not parallel with the clutch face could cause erratic cutting-out of the clutch. For a clearer description of pulser operation on a Subaru, check out: http://www.northursalia.com/techdocs/pdf/vent/tech.pdf

- Ian

Daeron is spot-on about checking the pulser. I think the reason my compressor clutch was disengaging as the belt slipped is because the slippage caused the compressor to turn slower than engine RPMs, thus signalling clutch disengagement. The pulser measures compressor RPMs somehow and (I assume) the ECU compares engine RPM values to compressor RPM values, and if the two are too far out of synch, voltage is stopped at the clutch. Supposedly this is to protect the belt from breakage if the compressor locks up? In any case, as Daeron indicated, a pulser too far from, too close to, or not parallel with the clutch face could cause erratic cutting-out of the clutch. For a clearer description of pulser operation on a Subaru, check out: http://www.northursalia.com/techdocs/pdf/vent/tech.pdf

- Ian

 

BONUS!! awesome link, there!! thanks a bunch, that one is bookmarked.

  • Author

Thanks guy's Ireally appreciate the tip's ,Does anyone know what the voltage should be at the pulse sensor plug? Or do you need an oscilloscope to check it?

also be sure to check the sight glass for bubbles. they should be very tiny if the charge is right

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