Subaru WRX STI 2.5L 2004, Oxygen Sensor by Hitachi®. This sensor is manufactured using the latest electronic-sensing technology to ensure accurate measurement of the concentration of oxygen in the exhaust gas. It is constructed to maintain peak engine performance, provide optimal fuel mileage, and make your vehicle emissions compliant.
- Ensures precise measurement of exhaust gas oxygen content
- Meets or exceeds OE specifications
- Designed for reliable and lasting operation
- Backed by a 1 year warranty
We hardly ever think about the oxygen sensors in our vehicles until we fail an emissions test. As an important part of the emissions control system, it measures the proportion of oxygen in the exhaust gas and sends a voltage signal to the vehicle computer, which adjusts the fuel injector on-time accordingly. If less oxygen is detected, the mixture is rich and the voltage signal to the computer will be above 0.45V. The computer will then lean the mixture by shortening injector on-time. When the mixture goes lean, more oxygen will be detected and the voltage signal will go below 0.45V, causing the computer to lengthen injector on-time. The signal from the primary oxygen sensor should oscillate many times per second as the computer controls the air/fuel mixture for optimal performance, best fuel economy and lowest emissions. Most modern vehicles are equipped with two oxygen sensors, pre-catalyst and post-catalyst. The post-catalyst sensor monitors catalytic converter efficiency. Its signal should be steady around 0.45V if the converter is operating properly. Oxygen sensors should be replaced when they get old and of course, when they fail. An old sensor will be slow to react and vehicle performance, fuel economy, and emissions will suffer.
If you need a reliable oxygen sensor that will optimize your engine's performance, Hitachi will provide you with a quality replacement part. The experts at Hitachi use advanced electronic-sensing and control technology and integrate hardware and software to provide improved fuel efficiency and reduce harmful exhaust emissions without sacrificing power, cost-effectiveness, or driving performance of the vehicle. This oxygen sensor will properly monitor exhaust gas oxygen content, allowing the computer to tune the air/fuel ratio for better fuel economy, reduced emissions, and smooth operation of your vehicle.
Since its founding in 1910, Hitachi has expanded well beyond the creation of the five-horsepower electric induction motor that was its first product. Today, it is a recognized leader in diverse market segments. Universally known as an Original Equipment Manufacturer that serves major carmakers, Hitachi is increasing its presence in the automotive aftermarket. Headquartered in Tokyo, Japan, Hitachi is famous worldwide for its reliability, innovation, and contribution to moving society forward. The company has pioneered a number of groundbreaking car parts, including the world's first engine central control units, photoelectric crank angle sensors, turbo chargers for rotary engines, etc. With operations in Japan, North, Central and South America, Europe, and Asia, Hitachi develops and manufactures advanced vehicle parts that preserve the environment, enhance safety, and provide comfort.