Air intake hoses are used to send controlled air to the internal combustion engine intake manifold. Worn or cracked air intake hoses can leak, which can impact vehicle operation negatively.
If an engine idles too fast, even after backing off the fuel injection or air bypass adjustment screw, air may be flowing past the throttle due to an intake hose leak. Under such circumstances, the air intake hose should be checked for looseness, and if signs of wear or damage are apparent it should be replaced.
A leak to the intake manifold can lead to a lean mixture, or combustion mixture, with an excessively high ratio of fuel, which can result in rough idling or even engine stalling. A whistling or sucking noise may indicate air being sucked in through the hose leak. Rough idling due to air intake problems often necessitates replacement of the air intake hose.
Numerous engine problems, such as stalling and poor performance, also can be caused by debris entering the air intake hose through openings or leaks. This debris, in turn, can enter the engine and cause serious damage. Correcting this problem involves an inspection of the engine and air intake hose.