Right tank fuel level sensor showing wild swings during flight home from KOSH. Suspect bad ground. Removed upper fairing and noted lock washer missing on sensor cap screw. Confirmed open circuit. Removed and cleaned cap screw and surface and re-installed with washer. Measured 0.78V or ~ 15 gal. Reinstalled fairing.

A/C stopped working during trip to KOSH. On return, confirmed compressor operation so suspected freon loss. Using freon charge line on manifold, added 1/4 oz UV dye and attached 12 oz (340 g) of Freon 134a. Bled air out of line. With high and low pressure lines attached, started engine and fed freon through low side to 250 psig high side pressure. Added ~ 10 oz (283 g), so lost about 0.62 lbs of Freon of initial 1.2lb charge. System cooling. Ran 10 min and checked for leaks but unable to pinpoint source. Will continue to run and look for leaks.