96 Altima - AC blows hot and cold - dealer mech can't figure it out

[azkami]

My Altima has been to the dealership service center three times now. I first thought I needed a new compressor, but they told me it was just the Thermister that was bad, and they fixed it. On the way home, it started blowing warm air again.

I took it back the next week, they had it overnight and couldn't find a problem. They also couldn't get it to blow warm for them.

It started blowing warm for me, probably once every 5-10 minutes of drive time. It will blow warm for a minute or two (sometimes longer), then slowly cool down again. Sometimes it will blow cold after I turn the A/C off for a minute, but this isn't always the case.

Dealer says the compressor is good - pressure is good. There are no leaks, both fans work, basically they've checked everything. I just picked the car up yesterday after leaving it for a week while I was out of town. They said they got it blow a bit warm once, but it never got hot for them. And they couldn't find anything else wrong. Well, twice today it blew air over 100 degrees (I live in PHX, AZ). I have a thermometer in my air vent so I can see the temp.

Does anyone have any ideas? If the dealership can't figure it out, any idea who can? And apparently, they had the manager of the service department looking at it, and even he couldn't figure it out. Thankfully they haven't charged me anything for these last two visits, since they couldn't find anything to fix. But I want my A/C working! I've had this car for over seven years now and have never before had an A/C problem. (sorry for the long explanation, but wanted to be thorough)

[timeskew]

Have the voltage to the compressor checked. It has been known to be too weak to engage the compressor's clutch. I had a similar problem, and was successful in running a direct line from the alternator to the A/C relay. This thread may help:

http://www.nissanclub.com/foru....html

[trixman]

I would go to http://www.autoacforum.com and copy and paste your question there.

They have techs that solve A/C issues everyday. Sounds more like a purely A/C issue than an Altima quirk.