Hello everyone!
I have brought a Lexus LS430 with around 150,000 miles a few months ago. As the weather was very cold back in my initial ownership, I thought the AC was functioning, but as I am currently getting baked driving around in this heatwave, it clearly isn't.
I have written down what I have done with this car in the following wall of text, so that it may help narrow down to the potential problem:
When I press the AC button, I can hear an audible drop of RPM from the engine, as if to show the compressor is functioning.
I went to KWIKFIT for a re-gas. The machine showed that it passed the leak test and was charged with around 900g of refrigerant. Still did not work. Whilst looking through the past service of the car, I found out that the car had its rear AC pipes capped off and filled with 700g of refrigerant. I took it back to KWIKFIT to drop the refrigerant to 650g; the AC still did not blow cold.
I took the drivebelt off and moved the AC compressor pulley, which was moving very freely without any sounds/resistance. I ran the onboard AC diagnostic test and received the only code of "00", which means no fault?
I recently had the "Change A/C Filter" code on the dash, way before noticing the AC not working. I took out the filter and reset the code to see if AC would work, but no luck.
I did the timing belt and water pump change myself on this car as soon as I brought it. During the works, I did have to loosen the bolts holding the AC compressor and move it slightly out of the way. Could I have pinched a line or whatnot?
I have taken the car to an AC specialist. He mentioned that it seemed the magnetic clutch was stuck on, therefore needing a new compressor. But after research, I find out that the LS430 AC Compressor does not have a magnetic clutch; it is a direct drive type. It seems he misdiagnosed the problem, which making me fairly hesitant on moving forth with what he said, as I don't want to ball out major ££££ to make a repair that does not fix the issue. I have visited further garages for second opinions and have been met with inconsistent thoughts.
I am quite stuck with this issue.
I thought it could be a common issue with the LS430, which can be solved easily. Is there anyone who experienced a similar story with my car? I am quite a handy person, so if there are a couple certain things the problem could be, I may be able to fix it myself. I just need some guidance.
Also, is there anyone that can recommend me an AC specialist that has some experience with the LS430 models? I live in Potters Bar and would commute quite a remarkable distance to have a solid diagnosis :D.