Parts for your 2012 Toyota Land cruiser-Knock sensor

2012 Toyota Land Cruiser knock sensor – what it does, where it lives, and when to replace it

Technical references from Toyota’s LandCruiser 200 Series repair manual and Electrical Wiring Diagram (EWD) for MY2012 show two knock sensor (KS) circuits on the petrol V8s (1UR‑FE 4.6L and 3UR‑FE 5.7L). The Toyota Electronic Parts Catalogue also lists knock sensors and a dedicated sub‑loom for these petrol engines. By contrast, the 1VD‑FTV 4.5L twin‑turbo diesel has no conventional knock sensor listed or shown in the EWD. So, a knock sensor is fitted and relevant to 2012 petrol LandCruiser models, and not used on the diesel.

On the 2012 petrol LandCruiser, the knock sensor’s job is to “listen” for detonation (knock) and let the ECU trim ignition timing on the fly. That keeps the big V8 smooth and strong on our variable Aussie and Kiwi fuels, protects pistons and bearings under load, and helps fuel economy on long highway stints.

There are two flat‑response piezo sensors, one for each bank, mounted in the V of the block under the intake manifold. Because they’re buried, they’re not a routine service item, Toyota doesn’t schedule periodic replacement. Still, they deserve attention whenever the intake manifold is off, or if there’s a check‑engine light with codes like P0325/P0330 or sluggish performance and higher fuel use.

• Access and replacement: Reaching them requires intake manifold removal. It’s smart to replace both sensors together due to the labour overlap, and to fit new intake gaskets and the KS sub‑loom if it’s brittle.
• Fitment tips: Use genuine‑spec parts, clean the mounting pads on the block, and torque to the workshop manual spec. Over‑ or under‑torque can skew sensitivity.
• Aftercare: Clear codes, check for updated ECU calibrations, and verify no vacuum or coolant leaks from the manifold refit. A short road test under light and moderate load helps confirm timing control is behaving.

If the vehicle pings only on poor fuel, the knock sensors will usually catch it and pull timing, but persistent rattle under load suggests other issues (fuel quality, carbon build‑up, cooling, or a genuine sensor or wiring fault). Diesel owners: that characteristic “diesel knock” is normal combustion noise and not managed by a knock sensor on the 1VD‑FTV.

Popular questions

Does a 2012 LandCruiser have a knock sensor?
Yes on petrol V8s (1UR‑FE/3UR‑FE), which run two sensors in the engine valley. The 1VD‑FTV diesel does not use a conventional knock sensor.

Where is the knock sensor on a 2012 LandCruiser?
On petrol models, both sensors are mounted to the block in the V under the intake manifold—intake removal is needed to access them. There isn’t one on the diesel.

Should both knock sensors be replaced at once?
Given the manifold has to come off, most workshops replace both sensors and the sub‑loom in one go to avoid repeat labour, along with new intake gaskets.