- 1). Remove the stock air box lid, generally secured with multiple spring-loaded metal clips. Lift the filter out of the air box and examine it for damage, collected debris, or other signs of wear. Properly clean and lubricate, or else replace worn air filters.
- 2). Check that all fitments and connections along the intake system are properly secured. This includes any plug-in sensors, intake mounting brackets, as well as the hose ring that clamps the intake tube to the throttle body. Tighten any loose connections.
- 3). Replace any worn gaskets or rubber fitments throughout the intake system. Being subjected to the extreme heat generated by the engine, rubber gaskets and pipe fitments are prone to cracking. This creates air leaks and/or unwanted intake noise. Generally, universal replacement gaskets can used to replace damaged stock gaskets. These can be found in various sizes at most auto parts retailers.
- 4). Examine any vacuum lines connected throughout the rest of the intake track, such as to the intercooler piping of turbocharged vehicles. Even though these aren't directly connected to the air box or intake tube, leaking vacuum lines can trigger various "check engine" error codes and/or other symptoms related to intake malfunctions.
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