Toyota A/C problem

[GAmes]

My wife has an '08 Toyota Sienna. Most of the time the A/C works as designed. Sometimes after 15 minutes of operation it stops blowing cold air, sometimes it is an hour. If I turn it off for 5 or 6 minutes then turn it back on it will blow cold air again. This happens in the high desert of NM so I don't think it is moisture freezing up the condensor. Can anyone shed any ideas what might be failing?

 

[Deleted member 995608]

Flux capacitor or the muffler bearing is my guess.

My thought too was the condenser freezing. These dawg gone vehicles are so complex anymore.

 

[DavidC]

You may want to nose around here for info

http://www.toyotanation.com/forum/274-2nd-generation-2004-2010/index15.html

Dave

 

[B.G. Smith]

Usually the first thing to check when the AC quits cooling but comes back after shutting off for a few minutes is low refrigerant charge, that would be the first thing I would check. Next time it does that if you can do it without getting run over I would raise the hood and look at the lines going into/out of the firewall to the AC, if it's freezing up there might be frost on the return line. bg

 

[fest3er]

*Evaporator* freezing.

Low charge should usually result in barely adequate cooling at best, and inadequate or no cooling when it's very hot and/or humid.

'08's not old enough for the evaporator to have gotten gunked up with mold and stuff, so it shouldn't be freezing up. Besides, if the evap is frozen, you should feel and hear a difference in air flow.

If I had to guess, and everything external checks out, I'd say there's water freezing inside the system, blocking coolant flow. If so, it'll have to be fully evacuated to remove the water.

 

[GAmes]

Well, I don't know. Today it worked perfect until we stopped for lunch and left the engine idling so the dog wouldn't have a stroke. Back on the highway, 15 or 20 minutes later, no cooling but air flow remained the same. I shut it off for 5 minutes then turned it back on and it worked perfect for the next 5 hours. Now that I'm home it will be awhile until I drive it again for any long distance. Thanks for the replies.

 

[BigPapa]

Hello Gary,

We're a long way apart here on vehicle models, but my '93 Sentra is doing the same thing. It's worse when it gets hotter outside. I'm going to replace the expansion valve. The system is fully charged and has a new compressor. The old compressor started leaking at the shaft.

Scott

 

[GAmes]

Thanks Scott. Since I don't know a condensor from an evaporator it is obvious that A/C is not my forte. When we went thru west TX a couple weeks ago the temp was over 100 and the A/C worked fine. It was the next day in NM when the temp was in the mid 80s that it malfunctioned the first time. Thinking back, that was also after the car had been idling for about 15 minutes with the A/C on. I wonder if there is a connection.