This little guy listens for engine knock – that's a pinging or rattling sound, almost like marbles inside the engine. It's a vibration sensor, really. It picks up those specific frequencies that indicate the fuel – air mixture is detonating instead of burning smoothly. It then sends a signal to the engine control unit, your car's computer. The computer uses that signal to adjust the ignition timing – when the spark plugs fire. Basically, it retards the timing a bit. Think of it like this: if the engine is starting to knock, the computer wants to slow things down a little to prevent damage. It's a crucial part of keeping everything running efficiently and preventing serious problems. It's a feedback system; the sensor tells the computer what’s happening, and the computer makes adjustments. It’s really important because uncontrolled engine knock can destroy an engine pretty quickly. It's like hitting your engine with a hammer repeatedly. The knock sensor acts like a shield, preventing that damage by telling the computer to adjust. If it fails, the engine could run lean and overheat, or experience significant internal wear. You’ll notice if a knock sensor goes bad usually through a check engine light, possibly accompanied by reduced power or poor fuel economy. Sometimes, you might actually hear the knocking sound itself, especially under load or acceleration. You can find these pretty easily online, places like Fixparts Online carry them, but it’s best to get it diagnosed properly first to make sure that is the issue. Buy risk-free: Knock Sensor (MPN 45940) is covered by a 3 year manufacturer guarantee!

About Febi

Ferdinand Bilstein is well known for reliability and is trusted by repair professionals worldwide.

Why Choose Febi?

• Febi parts are made to the same standards as original equipment, so you get reliable quality without the high price. • We offer a huge range of parts – everything from engine components to brake parts and even small wear items – all in one place. • Febi has been around for over 75 years, so we know what mechanics and drivers need to keep vehicles on the road. • You’ll find parts for many different makes and models, including popular European cars, making it easy to find what you need. Drive with confidence – choose Febi parts at FixParts Online.