Ive got a Lincoln mkz with the same symptoms you experienced on this post. Ive replaced the expansion valve twice, compressor twice, replace the condenser with integrated dryer. Have replace the compressor hose assembly (lo side and high side)which had a canister of some kind inline. Finally replaced the evaporator. It then would work up to about an hour then the low side went into a vacuum under throttle and not cool. After setting for a while it may work for a little while and do the same thing again. What fixed the one you worked on if you remember? please post on here as I do not have access to the owners email. Thanks for any responses, Mark

Mike Ryno
Owner
Tracys Automotive
Wichita, Kansas, USA