Originally Posted By: caravanmike
the technical term is "start up flare"
ryland i have a 3.3L (which is a de-bored and de-stroked 3.8l)
my best attempt on eliminating the start up noise, is the motorcraft filter FL1A. but if i were you i would experiment at every oil change with different filters since i don't know if their is enough room for the FL1A in a jk.
if it makes you feel better their are alot of 3.3L/3.8L's in the 400,000 mile to 500,000 mile range, which tells me the cold start noise is just that, noise (with no ill effects).
I imagine the noise is just clearances between the lifter, pushrod, rockers, and valve due to the lifters leaking down a little bit. Its louder on pushrod engines because the pushrods "clink" into their sockets on the lifter and rocker and make more noise than just the sound of roller-followers on an OHC engine with hydraulic lash adjusters (like my former 3.5 and current 2.4). If its happening just after sitting during the day, I'm not sure its really an ADBV thing. Lifters that wind up with some spring pressure on them when the engine stops (not all 12 can land with the valves fully closed) are just prone to leak down a little- no way around that. I've had superb luck with the ADBV on Purolator PureOne filters, probably a bit better than what I've seen on Wix in recent years.
My wife's PT cruiser takes a little filter smaller than my coffee mug. I verified that the baseplate is compatible with a full-size filter (FL1A, PL3001, etc.) but there's no way the bigger filter will clear a curve in the lower rail of the block. I need to buy a "shorty" version (the only number I ever remember for it is AC PF-20) and see if that will work- even a shorty is bigger overall than the tiny little OEM filter. At least it takes a full 5-quart fill, even with the tiny filter.