So I recently changed the air filter on this new-to-me car and of course found that the airbox thermostat was non-functional, and the engine has only been drawing air off of the exhaust manifold for who knows how long ... the bottom of the old air filter looked like toast.
IMHO the thermostat is an unnecessary weak link, if (when) it fails it's horrible for the car in many ways ... so I:
- deleted the whole valve
- cleanly blocked off the warm/hot air intake port
- removed the snorkel to guarantee loads of free-flowing cool air
- added a coarse screen, to prevent anything sizeable from entering the airbox, thereby enabling the air filter to do what it does best ... remove tiny contaminants from the air to promote long healthy MAF and engine life
Part 1 - Pull the airbox, remove the valve and thermostat and block-off the warm/hot air port: