Parts for your 2007 Toyota Highlander-Knock sensor

2007 Toyota Highlander knock sensor — purpose, lifespan and replacement tips

Technical references confirm the 2007 Toyota Highlander is fitted with knock sensor(s). Toyota’s factory repair manual for the 2AZ-FE (2.4L) and 3MZ-FE (3.3L V6, including Hybrid) details knock-sensor diagnostics and replacement, and the Toyota Electronic Parts Catalogue lists “Sensor, Knock” for both engines. The 2AZ-FE uses one sensor on the block beneath the intake, while the 3MZ-FE uses two sensors mounted in the V-bank under the intake manifold.

On this Highlander (also known as Kluger in some markets), the knock sensor listens for high-frequency vibrations caused by detonation (pinging). When it detects knock, it signals the ECU to trim ignition timing so the engine runs safely and efficiently. That means better drivability, protected pistons and bearings, and fewer emissions when running regular 91 RON petrol.

It’s not a routine “service item”, but it’s worth checking during major services if you’re chasing a Check Engine light, pinging, or odd timing-related behaviour. Common signs of a crook knock sensor or wiring include:

• CEL with codes such as P0325–P0334
• Pinging under load, sluggish acceleration, or poor fuel economy
• ECU running retarded timing as a failsafe

Replacement approach varies by engine. On the 2AZ-FE, the sensor sits on the block under the intake, access usually means removing the intake manifold. On the 3MZ-FE V6, both sensors live beneath the upper intake in the valley, so the plenum and related hardware need to come off. Plan for new intake gaskets, inspect the harness (it can get brittle with age), and route the loom exactly as per the manual to avoid false knock. Fit genuine or quality OEM-equivalent parts, keep the mating surface clean and dry, and tighten to the factory torque (around 20 N·m is typical—always confirm in the service manual).

A few easy habits keep the system happy:

• Use the recommended fuel, if it pings when towing or in hot conditions, try 95 RON.
• Fix oil or coolant leaks that can soak the valley on the V6.
• Scan for codes before parts swapping—knock faults are often wiring-related.

Look after the knock sensor and the ECU will do the rest—quiet, efficient running without the drama of detonation.

Popular questions about 2007 Toyota Highlander knock sensors

Where is the knock sensor located on a 2007 Highlander?
The 2AZ-FE 2.4L has a single sensor on the block beneath the intake manifold. The 3MZ-FE 3.3L V6 (including Hybrid) has two sensors mounted in the vee under the upper intake. Access on both engines typically requires intake removal.

Is it safe to drive with a bad knock sensor?
Short-term, the ECU usually pulls timing to protect the engine, so it’ll feel down on power and use more fuel. Keep driving with a faulty sensor isn’t ideal, misdiagnosed knock can escalate wear, and you may miss genuine detonation. It’s best to diagnose and repair promptly.

Do I need premium petrol to avoid knock?
The Highlander is tuned for regular 91 RON in AU/NZ conditions. If it pings when towing, heavily loaded, or in very hot weather, stepping up to 95 RON can help. Persistent pinging points to a maintenance issue—don’t rely on premium to mask a fault.