[JFP in PA]

I would start by doing a vacuum check on the new AOS. We have seen new units that were duds right out of the box. You need to check the vacuum level at the oil fill cap, it should not be more than 5 inches of water; any more than that and the AOS is bad. If you used an aftermarket AOS, I, would almost bet that is your issue; wwe have had zero luck with aftermarket AOS units.