AC was previously working - Compressor center not turning now - fan is fine - When I turn on AC I get a noticeable uptick in engine RPMs...but no cold air - thought I'd check/clean/reconnect the pressure switch but I've no idea where it is..Any insights? Video at Thanks,

 

So cleaned up connection from compressor to main harness(?) and compressor is now spinning when AC is on - still no cold ac yet and I'm not sure my cleaning resulted in spinning compressor- and I've been in and out off dash so much I may have screwed something up - maybe the pressure switch is behind glove? Do you guys want to see a gem of a 79 fully operational or not? (-*

 

If the compressor clutch engages when you turn a/c on, then the switch is doing it’s job. Sounds like you don’t have any refrigerant in the system.

If the 79 a/c system is anything like the 80-83 (my guess: it’s the same), then the switch is inside the evaporator box, you’d have to disconnect the lines, remove the box and open it up to access.

 

Hi Toy_tek and thanks very much - makes sense - yea it appears to be a leak - I added two cans of R134a and had AC for a week - then zilch. Thanks again,

 

Idk if you solved this problem and im not really an ac guy but if this is the stock ac system, you will have problems if youre not using r12

[Edit] i see your other thread...sorry.
Have you got it working now?

 

Hi swampedout & thanks - diagnosed this week w/ a manifold guage and Ferrari Mechanic (2 of em) friends who had a few choice words for Toyota tho they like the truck - "purged" system, and I'm separating lines to get to & replace pressure switch - I "ASS-U-ME" we'll fill with R143A(?) when complete but my intent is to keep stock system - Any specifics regarding your issues or any recommended R12 sources? Thanks,

 

https://www.hagerty.com/articles-vid...ts-and-the-law

Im just going off what little I know. I dont have a car with working ac. Id listen to the ferrarri mechanics over a internet toyota enthusiast/backyard mechanic.
But with that said what kind of people drive ferrarris? dont get me started

 

I believe you have to retrofit the R-12 system with R-134 o-rings and seals or the R-134 will leak right out.

 

LOL...damn F-car guys.

 

Hi & thanks, believe the R-134a will not require new/different O-rings - removing evaporator to get to pressure switch and removing drier per friends' guidance - waiting on a a 29mm wrench to disconnect large nut on low pressure line at firewall. Will investigate your above -