Fixed AC last summer and now not working again (1 Viewer)

[profro]

I replaced my AC compressor, dryer, belt, idler puller and fully recharged the system last summer. It worked great and blew almost too cold. I used either Denso or Toyota parts.

Jump to today, I tried the AC and it just blew warm air. I got home and checked fuses. All were fine. I looked under the hood and saw that the AC clutch was not engaging. I tried to jumper and it sparked and wanted to kill the engine.

Any ideas?

 

[scottryana]

The expansion valve seems to be the most frequent problem with the A/C.

 

[yohavos]

Make sure the system is charged--the AC clutch won't engage if it's too low. You may have had a slow leak.

 

[profro]

I will certainly check those, but do either of those explain not being able to engage the clutch manually or doing so causing the engine to almost die?

 

[96Cruiser]

I will certainly check those, but do either of those explain not being able to engage the clutch manually or doing so causing the engine to almost die?

just a wild guess, but could the compressor be locked up, causing the engine load when you manually engage the clutch?

 

[SUMMIT CRUISERS]

Try engaging the clutch like you did without the engine running. Then try to turn the pulley by hand. You may need to loosen the belt to make it easier. As @96Cruiser mentioned it may be locked up.

 

[george_tlc]

Engaging the compressor will load the engine. Often the ECU etc will idle up the engine when it tries to engage the compressor.

I'd drop/loosen the belt on the compressor if you are worried, manually jumper it and see if you can rotate it by hand.

Set of gauges will tell you if you have lost refrigerant.

cheers,
george.

 

[profro]

I certainly hope a 1 year old Denso compressor isnt locked up but that seems about my luck with this truck. I'll try tonight after work. Thanks for the suggestions.

 

[jvazquez53]

Bet the evaporator went bad...

 

[profro]

Ok, took belt off and energized compressor direct from battery with engine off and locks up like it's supposed to.

What next?

 

[george_tlc]

Ok, the compressor clutch locks and presumably the compressor isn't seized the next step is to check you have refrigerant in the system... set of gauges would be useful...

cheers,
george.

 

[SUMMIT CRUISERS]

Ok, took belt off and energized compressor direct from battery with engine off and locks up like it's supposed to.

What next?

"locks up? " Does the compressor turn with the clutch locked up or is the compressor locked up? You probably have a leak in the system if the compressor turns. To find the leak, either add a can of freon and spray soap/water on all the o-ring fittings or add air into the system through a set of gauges and do the same. On my son's 92 we had an o-ring leaking on the passenger front condenser location. If needed, a generic set of AC o-rings can be purchased at any auto parts store.

 

[profro]

To be clear, with no voltage to the compressor the clutch does not lock the pulley to the compressor. When I apply voltage, the clutch locks the pulley to the compressor. Thus when I spin the pulley by hand, the compressor also turns.

 

[SUMMIT CRUISERS]

To be clear, with no voltage to the compressor the clutch does not lock the pulley to the compressor. When I apply voltage, the clutch locks the pulley to the compressor. Thus when I spin the pulley by hand, the compressor also turns.

Ok, that is all working properly. Now on to find the leak.

 

[1972FJ55]

Any chance you added dye to the system when you replaced the parts? If so, a UV light might point out the problem area. Don't pressurize the system with air, better to use some R134a. Also look for oil residue at any connections as it can indicate a leak. As George said, put a set of gauges on it to see if it's low/empty.

 

[jeffro109]

Most likely just a leak and too low freon amount to let the compressor come on. There are several o-rings that can be easily replaced on the compressor when it is recharge time, use or have the repair person put some leak dye in to be sure where the leak is rather than chase it.

 

[profro]

I added the proper PAG and r134 only when I replaced the compressor and dryer last summer (with all new associated o-rings). I don't see any oil residue anywhere obvious. Unless the dye is in either of those I guess there isn't any. It pulled great vacuum last summer and blew super cold for months, which has me scratching my head on a leak. But I'll check into having someone dye check it and I can do an on vehicle inspection of the pressure switch.