Hello Everyone.

I have an 05 TL and owned it for around 2 and a half years. I'm the second owner and the car has 182k miles. I've never had any issues with the car until now. So basically what's happening is that my A/C is blowing hot air. I realized this when driving home from work one day. The next day early in the morning when it was cooler and I started the car and turned on the A/C it was ice cold and after driving for 10 minutes it went hot again. I've taken it to 2 mechanics to get it checked out. The first one said that it's not a coolant issue because according to them my tank is full and they said I need a new compressor and quoted me $975 for the job. The second mechanic said something along the lines of my tank being able to hold 19 (some unit) and my car currently had 8 (some unit) which contradicts what the first mechanic said. The second mechanic flushed my system and added more coolant and that didn't seem to fix the problem so he didn't charge me for anything. Has anyone had a similar problem or has any pointers on all the possible other parts that could be the issue before I go out and spend that much money to get the compressor replaced.

links to parts and pricing would be very helpful.


P.S first time posting here and sorry if I added too many details if not useless details, just want to be as specific as possible.

 

More than likely your field coil in the compressor is failing, I had the same issue, it could possibly be the relay that gives power to the field coil as well. The typical shop repair would be to replace the compressor, however the DIY way is typically to replace the field coil in the compressor. Which I did personally and it takes a while and some tools and knowledge, but it is cheaper.

I am not sure how much you are willing to do on your own, but you are better off finding a shop that literally only works on A/C systems, they usually can figure out A/C issues easily if you aren't confident doing some testing/work on your own.

One thing you could check yourself is when the A/C quits blowing cold air, pull over safely to a parking lot and pop the hood while the car is running and the A/C is running and see if the compressor is clutch is engaging. If not you can try swapping relays in the under hood fuse box (with the car off) and see if that makes a difference. Then if you really feel like having some fun you can use a multimeter to test the ohms of the field coil, more than likely its failing internally when it gets hot and will show an infinite reading (meaning incomplete). You can also jump power in the relay box for the relay that controls field coil when the car is hot, A/C not blowing cold, car turned off and listen for a clicking sound of the A/C compressor clutch engaging.

If you have already had the system refrigerant checked (which sounds like you did?), then more than likely that isn't an issue.

If you want to go the compressor route, you can pick up a Denso (OE manufacturer) compressor on rockauto.com for about $200, most shops will let you bring your own parts. As far as I am aware the only way to get a field coil and/or clutch for these compressors is through Acura/Honda, which is what I had to do. I bought both for around $300 about two years ago, you have to remove the clutch to get to the field coil, so I figured why not I am already there. The plus side to replacing just the field coil and/or clutch is you don't have to pay to have the system evacuated and recharged, so its a bit more for parts, but it can be cheaper in the end. But most shops won't change just the field coil.

If you search on the site for field coil and A/C issues you will find several threads with discussions similar to your issue/question.

 

My car did that last year where it would intermittently blow cold air and stop. First simple thing to check would be to check the relay (fusebox underhood). If you go to your local dealership, you can get the A/C relay. For some reason the new relay was quoted at $24 (i know). See if that makes any difference.

The issue in mine was not with the compressor but with the clutch set and stator coil. My mechanic did this to diagnose -

1. With the engine off, he reached down to the compressor pulley and tried manually rotating the compressor. He wasnt able to. He said, it was the clutch set that was bad.
2. He checked the current draw in the relay socket with the AC on full speed. He said the compressor is getting power but unable to engage because of the bad clutch.
3. He checked the freon levels to make sure it has sufficient coolant.

He then asked me to get the following part numbers -

38900-RCA-A01 CLUTCH SET
38924-RCA-A01 STATOR SET

Replaced it and it all worked fine.

HTH.