enilno123

I have a 2002 LX470 with the A/C not blowing cold air. The A/C indicator on the nav screen blinks off and on and at one point saw a message displayed that says "check a/c...". The message was only displayed briefly and it no longer shows up, but the flashing A/C indicator still occurs.

For a brief period of time, this problem went away and the air came out very cold so it doesn't seem to be an issue w/ the freon. On a couple of occasions but not too often, the rpms would fluctuate almost as if the compressor is turning off and on repeatedly.

Any thoughts on whether this will require a compressor replacement? Or should a clutch or relay replacement be tried first, or perhaps a freon charge.

Any comments appreciated.

kwatt1

The system is low on Freon. It's got enough to start the compressor. This is quite common when you loose Freon.

First thing you need to do is find the leak. Almost always it's the compressor but it can be anything. If you take it to a shop you are looking at easily $1000 job. Without a Freon leak tester, your next best bet is a leak detector Freon from an auto parts place. Read the instructions on how to find the leak; usually its some sort of dye. Get a can of it (usually comes with the appropriate hose required to fill the system) and put it in the system and run the A/C for a while. Look for the die. You'll likely find it at the high pressure cut-off or the seal. but it could be anywhere.

A few points
- NEVER run the A/C when you fill it unless you REALLLLLY know what you are doing. You will not be happy if the can blows up in your hand. It will hurt!
- don't bother adding Freon to keep it running unless you are just plain stuck and need the A/C. Depending on how severe the leak is, it will be gone quickly. The parts places will try to sell you all kinds of stuff and convince you that its ok. It's a waste of money and Freon is not cheap anymore.
- If you need to replace the compressor and you are going to keep the vehicle for a while, buy a new one. They can be acquired for less than $300. Use the OEM Denso.
- If there is a problem with a leak, don't force it to run. Doing so will only cause the compressor to fail. When that happens you will have metal fragments in the system and a mess to clean up to fix that.

I've not removed the compressor on my LX, but it looks to be in a tight space and would require patience. Replacing the compressor means replacing the accumulator and the orifice tube and SHOULD require adding an inline filter. If you don't have the vacuum pump and manifold gauges an indy would charge maybe $200-300 to evac and refill.