||With just over 100K miles on the odometer, I recently replaced the original fuel pressure regulator and fuel pressure damper on my Z. I always considered these components either working or NOT working. And if they had gone bad, the results would be obvious (e.g. catastrophic fuel starvation at speed, or a fuel leak).
My car was running fine before the change, but I opted to replace them anyway -- just "because," I suppose.
Maybe it's a placebo effect, or maybe I should chalk it up to driving in slightly cooler weather... (Or maybe I inadvertently fixed a boost leak I didn't know I had.) But HOLY SHIT! My car seems to pull a LOT harder now. And the idle is buttery smooth. It was smooth ~enough~ before, but now it's BMW 12-cylinder smooth.
Has anybody else noticed that much of a difference from replacing such simple fuel line maintenance items? In terms of degree of difference, I'd say it ranks with installing a fresh set of O2 sensors.