The temp. rise sounds normal to me, however, the lack of cold air could be due to the loss of freon. You may have a leak somewhere. You should take it to a tech, they put some kind of infrared dye in there and they can tell if and where you have a leak, then they can fill it back up with freon.

Just my opinion.

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'89 420 SEL
'90 300 SEL
'84 300 SD (sold it)