AC intermittently working

[Skyehunter]

I have a 98' SR5 4Runner 4x4 auto 3.4L. Just did an ac recharge from a 16 oz can due to ac cutting out. It worked for a few days after fill then stopped for one day, worked the next few days, then stopped again today. When it works it blows good COLD air, nothing but ambient air when not working. Any suggestions on where to go from here? Fletcher guys said something about a switch in the engine compartment??? The compressor seems to shut on and off every 15 to 30 seconds while the dash switch is in on position, dash light does light up correctly??? Do i need more 134A??? ANY SUGGESTIONS?

 

[Singtoe]

You have to look at your sight glass. It is a little window into your freon system. You will need a flash light and look and see the freon in your system. If it has a lot of bubbles in it , you need more freon.

You probably have a leak in your system.

You really should take a spray bottle with some soapy water and spray everything down that is ac related. If there are in leaks you will see bubbles. Check all the connections and spray the condenser down too.

 

[wardriver]

You probably have a leak in your system.

What Singtoe said.

If the leak is in an o-ring you might be able to bring it back to life with a can of freon w/ sealer. One can will run you about $20 with a cheap-o gauge at Wal-Mart. You can also get a can of freon with yellow dye in it. Run it for a while and you can find the leak with a black light.

 

[TN22Corps]

Sounds like my leak.

As Singtoe knows, I'm having the same symptoms, verbatim. I just had a compressor, drier, and expansion valve put on, and freon topped off. Blew cold for 2 days, then the AC only blows ice cold for the first 10-15 minutes of running the vehicle, after that it's more like outside air.

I have been lucky enough to see that I have an easily fixable leak in the liquid line (running in front of the radiator).

See:
http://www.toyota-4runner.org/3rd-gen-t4rs/86676-ac-diagnosis.html

 

[Skyehunter]

...I did a soap check before i did the fill a few weeks ago, no obvious leaks. I also physically checked all lines and places where there are connections, no obvious leaks. I did notice while i was filling the system with 134a that there were alot of bubbles that would show up while compressor was running..Thinking probably low with slow leak as well. thanks for suggestions.

 

[Skyehunter]

Just in case someone else finds this thread with the same issue. It appears it was the Expansion Valve. Pulled her apart yesterday swapped in a new valve and did a good long evac. Nice cold air Thanks for all the help, time to get back on the trails without eatin all that dust. Now hopefully she stays cool arty: