The truth about cold air intakes according to one auto manufacturer.
Cold Air Intake Systems and Low-Restriction Air Filters:
Cold air intake systems and low-restriction air
filters are hot aftermarket accessories. Popular
among the import tuner crowd, these items may
improve engine performance by letting the
engine breathe more deeply, reducing the intake
air temperature, and cutting down on weight. And
for that all-important sound when you wind up
the engine, cold air intake systems help produce a
deep, throaty tone.
Stock air intake systems are designed to clean the
intake air, minimize intake noise, and keep water
from getting into the intake tract, all the while
putting out the most horsepower and torque.
Although cold air intake systems and lowrestriction
air filters kick up engine performance a
notch, they also have their dark side. They can
really mess up the engine, and that’s not covered
by warranty!
With cold air intake systems, you run the risk of
engine damage from hydrolocking if you drive in
wet weather or plow through standing water.
These systems are usually designed to draw air
from the bottom of the engine compartment or
from the front of the radiator where the air is cold
and dense. The air filter used in these systems
doesn’t sit in an air box, so water that gets sucked
into the filter gets sucked right into the engine.
When enough water gets into the engine, the
piston can’t fully compress the air/fuel mixture
(water doesn’t compress) so it stops before
reaching top dead center (TDC). Even though the
piston stops, the crankshaft just keeps turning
from inertia. As a result, the connecting rod bends
and gets shorter. With each compression and
power stroke, the connecting rod flexes until it
eventually fails from metal fatigue.
With low-restriction air filters, you run the risk of
premature engine wear and contamination. Some
of these filters just don’t work as well as stock air
filters do. Microscopic debris can get past the
filter, causing premature wear of the pistons,
piston rings, cylinders, and valves. It can also foul
up the throttle body and the components of the
intake manifold runner control (IMRC), intake
manifold tuning (IMT), and idle air control (IAC)
systems.
So what’s the bottom line here? Tell your
customers they’re taking a really big risk if they
run the
vehicle with a cold air intake system or a
low-restriction air filter. Engine damage caused by
these items isn’t covered by warranty, and that
could take a big bite out of their pocketbook.