TXAgZ28

iTrader: (1)

Recently, I noticed on a long trip that after a while, my air conditiong would blow extremely soft even when set on max at the max blower speed. The air was ice cold, just not enough coming out. So I replaced the cycling switch after getting some advice from a friend that works at a GM dealer. I replaced the switch, and went on another long trip and noticed it happening again. This time it didn't happen as bad (was hotter outside, if that matters) but I could still tell a noticeable difference in blower force on max settings. Air is still ice cold, just weak...

It doesn't happen when I drive around town as much as when I drive steady hours on the highway...

Any ideas?

It's a 2001 Z28 M6 w/34k on the clock. Only engine mod is a lid.

jimmyblue

iTrader: (11)

Evap icing I'd expect, starting to obstruct the
airflow. Probably depends more on humidity
than air temperature. If you turn the 'stat
to a full-warm setting for a few minutes (but
still on A/C setting) and airflow gets better
again, this is your problem. Might want to not
use the full-cold-cranked 'stat setting, if it's
trying to force a sub-freezing output that
might be the root of the problem (A/C output
should be just above freezing so ice is not
formed).

TXAgZ28

iTrader: (1)

So if it is icing, what is the cause other than a cycling switch not disengaging the compressor?

GMoney

Low freon will cause icing as well

TXAgZ28

iTrader: (1)

But wouldn't low freon also produce not-so-cold air?

GMoney

Not necessarily - but it makes the compressor work too hard which is one reason the coils ice.