hi folks, my first post here. looks like a good community. I'm hoping you can help me with an ac problem.
I just bought a 1991 ls400 with 133k miles that has been sitting for 3 years due to owner's health and has done less than 5000 miles in the last 7 years according to Lexus service mileage records. It has an undated r134a conversion sticker indicating a no lexus shop converted it and added 29 ounces of r134a and 4.5 ounces of oil to it. The owner's wife cannot find the receipts and all she can say is that was more than 3 years ago.
the AC light works and does not flash but turning it on makes no difference to the temp coming out of the vents.
I also pulled the ac trouble codes using the instructions here.
http://www.lexls.com/tutorials/air/accodes.html
I get code 33 which apparently means "Open in air mix damper position sensor circuit. Or, open or short in air mix servomotor circuit. Or, air mix servomotor locked."
my first question is is this a normal code for a system that is low on coolant or is that an indication of a specific problem and, if so, what problem?
my second question is whether 4.5 ounces of oil sounds right to you? I would have though more like 8 ounces from limited experience with other systems.
You cannot buy r134a do it yourself kits in canada so I need to get an AC tech to look at this. I had been thinking I would try topping it up with coolant and dye first to see if that is the problem. Now with this code I am not so sure and I am also wondering whether to tell the guy to add some oil. any help is much appreciated.