I posted a thread about not too long ago on this problem and Gary and I pondered wildly for quite awhile... Just to get to the conclusion from all my observations, this is what appears to be the issue: used 2 wix/napa filters that had higher startup pressure during mornings vs pureones. Didnt use it back-to-back. Went with one, then switch off to pureone, then back to napagold, then back to pureone. Used same weight oil GC 0w-30 throughout. Weather doesnt affect the pressure at all. I have proven this many times already with temperature ranging from 25F to 70F from warm Oct.- cold Dec. This is not recent, it's been like this since day 1 of using pureone. I have to look back at my book for the psi number, but i assume lower pressure is better? Some Titan owners experience this problem too when switching off their pureone to a wix or vice versa. Im just wondering if any of you have this similar situation or is it just me and the Titan that does it...