I too have been suffering with the AC not cooling very well. First it was the leaking vacuum lines and the air switching flow the vents to the defrost (they still don't work as they should). But the air just blows a little cooler than ambient. Lately we've had some scorching temps in Atlanta and the truck AC just does not do it... I had a mechanic look at it and they added freon to it. It seemed to cool just a tad better, but still no cigar. It does seem to almost blow cold when driving on the highways at cruising speed but in the city traffic it's pretty useless. My compressor looks like it's new. I don't know about the rest of the stuff. Where exactly is the condenser that should be cleaned? Is it behind the radiator? Please excuse my questions but I don't want to make incorrect assumptions. Ignorance can be cured

Oh yeah, when the outside temps are in the low 80's or high 70's, it blows freezing cold air.. But of course, that's when I rather roll the windows down and save gas....

 

My condenser is actually in front of the radiator. Not sure if that's the same for all years, but at most it'll be behind the radiator. Just follow the lines out of the compressor.

I had the same "defrost" problem you described, but ever since I fixed the one plastic line, it's blown through the vents steady and hard, just not cold.

 

I repaired 2 lines. The one that went to the vacuum actuator near the fender in the corner of the firewall as well as the one that entered the plenum just to the left of the engine. Still I get the vents shunting to the defrost when I accelerate of maintain the throttle under load. Perhaps that first tube is damaged in more places my repairs are leaking....
BTW, tonight the air was blowing nice and cold once I got going good . Of course, it's much cooler out that the upper 90's we had during the day....

 

Yep. My repairs leaked at first too and my air still swapped... but just so we don't change subjects mid-stream, check out my fix in that thread (A/C changes outlets/vents on its own - '91).

 

So, I leaked some 134 out of my system, down to about 30-35 psi. It seems to be making colder air now, but still not quite "ice". Is 30-35 a good range for the 134? Any other ideas on tweaking this thing?

Thanks!
Bryan