Parts for your 2001 Toyota Crown-Knock sensor

2001 Toyota Crown Knock Sensor — What It Does and When to Replace It

Yes, the 2001 Toyota Crown is fitted with a knock sensor. Technical sources confirm it across the S170 series engines. The Toyota Electronic Parts Catalog (EPC) lists a “Sensor, Knock” for JZS171/JZS173/JZS175 (1JZ-FSE/1JZ-GE), GS171 (1G-FE), and UZS171 Majesta (1UZ-FE). Toyota service literature for the S170 Crown engine control system also shows the knock signal as an ECM input and includes diagnostic trouble codes P0325/P0330 for knock sensor circuits. Toyota’s New Car Features documentation for these engines describes knock control as part of ignition timing strategy.

On this Crown, the knock sensor’s job is simple but crucial: it listens for detonation (pinging) and lets the ECM trim ignition timing to protect the engine. That keeps the straight-six (or V8 in Majesta) smooth, safe, and efficient on everyday 91–98 RON fuel found across Australia and New Zealand.

As part of servicing the 2001 Toyota Crown, it’s worth giving the knock sensor and its sub-loom a health check, especially as heat and age can harden insulation and cause intermittent faults. Symptoms of a crook sensor or wiring include lazy performance, worse fuel use, pinging under load, or stored codes like P0325/P0330. If the sensor fails, the ECM often swings to a safe, retarded timing map that makes the car feel doughy.

Replacement is straightforward but a bit fiddly on the inline‑six because the sensor(s) live on the block beneath the intake manifold. Many Crowns run two sensors (one for cylinders 1–3 and one for 4–6), the 1UZ‑FE V8 also uses a pair. Access typically means removing intake hardware, so planning gaskets and hoses is wise.

• Use quality OEM-equivalent sensors (Denso is the usual OE).
• Inspect and, if needed, replace the knock sensor sub‑loom at the same time.
• Clean the block’s mounting land, install the sensor dry and torque to spec (Toyota inline‑six engines are typically around 27 N·m). Don’t overtighten.
• Route wiring exactly as per factory to avoid vibration damage.
• Clear codes, then road‑test under load to confirm no pinging and normal performance.

Look after the knock sensor and it quietly looks after the engine—keeping timing spot‑on, power up, and the Crown feeling every bit as refined as it should.

Popular questions about the 2001 Toyota Crown knock sensor

Where is the knock sensor on a 2001 Toyota Crown?
On the S170 inline‑six engines (1JZ‑FSE/1JZ‑GE/1G‑FE), the knock sensor(s) are bolted to the engine block under the intake manifold—generally between cylinders 2–3 and 4–5 on two‑sensor setups. On the UZS171 Majesta 1UZ‑FE V8, they’re mounted in the valley beneath the intake manifold.

What are common signs the knock sensor needs attention?
Owners may notice sluggish performance, higher fuel consumption, pinging under load, or the check engine light with codes P0325/P0330. Often the ECM shifts to a conservative timing map when it can’t trust the sensor, so the car feels flat until the fault is fixed.

Should they choose OEM or aftermarket?
OEM or OEM‑equivalent (Denso) is recommended for accuracy and durability. Cheap units can be noisy or insensitive. It’s also smart to inspect or replace the sub‑loom, use the correct torque, and follow the factory wire routing to avoid future false knock or open‑circuit faults.