Hi Mike, I never had the exact same problem but I would check all the altitude chain both mechanically and electrically, the connectors in and out several times, the way the altitude encoder is fixed, centered. Maybe the difference between day and night is linked to the temperature drop at night. I recommend to have a look at the tutorial of Scott Tannehill to confirm that your altitude encoder is well centered too. Another thing to check is the tension on the altitude cable. Good luck Fr¨¦d¨¦ric?
Fr¨¦d¨¦ric Ruciak