Once you get past the basic pieces - plugs, air filter, keeping the tires correctly inflated, 4 wheel alignment- you'll also want to make sure the TB is clean (make sure to use Fuel Injector spray, not carb cleaner), the MAF is operating correctly, the Cats (all three of them!!) aren't clogged up with age (thus restricting exhaust flow), all of the various vacuum lines are intact - and not cracked due to age, thus creating vacuum leaks, the PCV valve is operating correctly, and the O2 sensors are functioning correctly.
What I'm finding is that a lot of the various lines - emissions, vacuum, electrical have seriously gone brittle on my SVX after 13 years and 186k miles!
-Bill
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Retired NASA Rocket Scientist
Most famous NASA "Child" - OSIRIS-REx delivered samples from asteroid BENNU to Earth in Sept. 2023
Center Network Member #989
'92 Fully caged, 5 speed, waiting for its fully built EG33
'92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension
'92(?) Laguna, 6 spd and other stuff (still at OT's place)
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