Sounds like all you are missing is the pre-heat hose. We usually take them off. There is an air filter box thermostat, which in theory opens a fresh air vent when the air gets too hot to send through your air mass meter. Problem is...when this cheap teeny tiny part fails, it takes your air mass meter along with it. Rather than worry about it failing...we take off the hose.

to answer your question...the pre heat hose is useless unless in cold temps. It allows the engine to heat up faster in cold temps. I beleive the thermostat in the air filter box begins to allow heated air in...at around 40 degrees F or lower. It sometimes jams opens(the thermostat in the box) and allows heated air to continiously flow insde....damaging the air mass meter (expensive part) as well as causing other perfomance problems. I woudnt' worry about the hose unless you are in a state that requries it for emissions testing. I woudl check the thermostat to see if it's stuck open as well(only if the temp is above 40 or 50 shoudl it be fully closed).


About the other hose. Connected to the air filter box there are two hoses. One extends towards the front (outside) of the car towards the grill. this is the hose that sucks in air. This hose is not connected to anything...it's simply to draw in air. Then there is another hose that goes from the part of the air filter box all the way to the intake manifold(this is the hose that is towards the inside of the car rather than pointed towardst he outside. All parts of this hose going towards the intake manifold need to be on snugly. If its not connected its allowing unfiltered air in which will lead to somewhat more engine abrasion and wear.


Anyways...good luck

I think you may be talking about the intake duct. This is a plastic peice that takes air from outside the engine compartment. I have taken mine off as I believe it to be fairly useless. It actually inhibits airflow very slightly and was put in to lower intake noise. The preheat hose is also fairly useless except here is California where it is required for smog. I've wired my heater flap in the air box closed.
--
Simon 80 240 296k 17 years.

That hose needs to be connecting the air filter to the mass airflow meter. Driving without an air cleaner greatly increases the wear rate of certain internal engine parts, ie: piston rings, pistons and the cylinder bore. It can also shorten the life of the mass airflow meter ($180.00 or so)and cause some subtle drivability problems. Fix it as soon as you can if you don't want to greatly reduce the life of your car.

It's supposed to lead to the preheater nipple on the exhaust heat
shield. Don't bother, but open the air box and use a screw and
some large washers to jam the flap so as to cover that hole (remove
the thermostat). Unless it gets very cold (like -10F) regularly
where you are, or your state has underhood emissions inspections,
the hose is pretty useless.


-b.