The AEM Electronically Tuned Air Intake system is the next generation of intake technology. With its revolutionary ETI module, AEM has successfully solved a problem without reducing performance. The problem relates to the Mass Airflow (MAF) sensor, which on most modern fuel injected vehicles determines the airflow rate into the engine and meters fuel accordingly. The problem occurs when the intake tube diameter is increased, as is common on aftermarket performance air intake systems. When the tube diameter is increased, airspeed is reduced, which affects the MAF sensor signal and could possibly cause a CHECK ENGINE light. Many intake manufacturers reduce the diameter of the tube at the MAF sensor location in order to maintain airspeed so the MAF will not be affected. However, reducing the diameter creates a restriction and reduces airflow into the engine. AEM has chosen an alternative approach that maintains intake tube diameter and results in more airflow into the throttle body. The ETI module electronically communicates with the MAF sensor to ensure that the proper amount of fuel is delivered even with a larger diameter intake tube. The AEM system ensures optimal airflow and fuel delivery. Like all AEM air intake systems, the AEM Electronically Tuned Air Intake system is made in the USA and backed by a lifetime warranty.