I have a 2000 v6 4wd that has lost it's ability to keep us cool! I've tried replenishing the refrigerant a couple of times but that doesn't help. I searched for a thread I thought I saw last year about other parts that go bad but I have failed to find it.

Thanks for the assistance!

Inject UV dye with the new refrigerant...then look for the leak(s) with a UV light.

The upper aluminum line along the firewall is a common place to look btw.

The "Thermo Control Amp" likes to go bad, but I'm pretty sure when that fails the AC completely stops cooling - it sounds like yours is kinda working.

Anyway, you might want to search old threads for the TCA just to learn about it.

I've only ever had two AC problems in my '00 - the TCA went bad, (fortunately that was like a $40 do-it-yourself fix) and one of my freon hoses split.