I drive a 1998 Lexus GS400 , and I recently did my major tune up. Timing Belt, Water Pump, spark plugs, etc. Now every time I turn on my air conditioning , a clicking noise appears every time I press down on the gas pedal. I was told that the AC Converter is out, but my mechanic told me to just put a little PAG refridgerant coolant oil to see if that helps. I bought the PAG oil for $10.00 instead of paying $600+ for a new converter. I always like to start with the little things that might prevent me from paying the big bucks in every way possible. There are 2 types of PAG oil. PAG +134, and PAG +150. The higher the number, the thicker the oil is. I chose the 150 because I believe the converter needs a lot of lubrication. Can anybody tell me how to change the PAG oil? Where do I pour it in and how much do I pour?. all thoughts are welcome. Thank You

-Mr. Bay

#1 unless you have a full compliment of A/C tools, vacuum pump, manifold guages... recovery machine... etc. AND know what to do... you aren't going to be doing it.

First off,

#1 there is no such thing as a A/C converter...

#2 if you misunderstood him and he said "COMPRESSOR" you still don't simply put in some PAG oil.

It's a sealed ssytem... it just doesn't leak out, period. The refidgerant gas would have escaped long before it got to that stage and pressure switches would have shut the system down.

Overfill the system and you destroy the compressor when it slugs. Oil CAN be put in while the system is pressurized but that takes a special tool. Open the system to the air and you MUST replace the Reciever/Dryer, and evacuate the system with a vacuum pump to remove air and moisture.

Personally it sounds like your mechanic is trying to rip you off.

I do hold a Section 609 MVAC license. While I may not be an A/C guru and all knowing in that field... I do know enough to do this work, have and can spot someone who is getting taken for a ride. If the compressor is making noise because its worn out... more oil or thicker oil won't fix it.

I think you mean "compressor", not converter.
If the A/C compressor is noisy, sometimes adding lubricating oil will quiet it some, but won't fix the problem: the compressor is worn.
Also, any oil simply added to a functional A/C system cannot be just poured in. The system is pressurized and a special tool is needed to inject, under pressure, the oil.
Unless you have the skills and tools to do this, you'd best leave this to someone who does.