What Is a Knock Sensor?
The knock sensor protects your engine from damaging detonation. A Cranbourne West specialist explains.
What it is & what it does
The knock sensor listens for “knock” (pre-ignition/detonation) in the engine and tells the computer to adjust the ignition timing to prevent it. It quietly protects the engine, especially under load or on lower-octane fuel.
It’s why a car designed for premium fuel can run (with reduced performance) on regular — the knock sensor pulls timing.
Signs of trouble & how we help
A faulty knock sensor can cause a check-engine light, reduced power and economy (the computer runs conservative timing to be safe), or in rare cases allow damaging knock. It’s usually a contained replacement.
We read the fault data to confirm the knock sensor before replacing it, and check there’s no actual knock cause (like wrong fuel).
Questions about your car? Just ask.
Understanding what’s under the bonnet makes servicing decisions easier — and we’re always happy to explain what your car needs and why, in plain English.
Book a service or a check with a Cranbourne West specialist online in 60 seconds, or call 03 8782 0711.
What Is a Knock Sensor? — FAQ
It detects engine knock and tells the computer to adjust timing to prevent damaging detonation.
A check-engine light, reduced power and economy (conservative timing).
Usually not urgent, but it can sap power/economy and rarely allow harmful knock. Worth fixing.
Using lower octane than specified causes knock the sensor compensates for — we check that too.
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