Parts for your 2001 Honda Odyssey-Knock sensor

2001 Honda Odyssey knock sensor – what it does and when to replace it

Yes, the 2001 Honda Odyssey is fitted with a knock sensor. This is documented in the Honda Odyssey Service Manual for 1999–2004 models (PGM‑FI/Engine Control section, DTC P0325 Knock Sensor Circuit), and it’s also shown as a catalogued part in Honda’s electronic parts listings for the J35A1 3.5‑litre V6. The OBD‑II definition SAE J2012 lists P0325 as the knock sensor circuit fault that owners commonly see on this model.

The knock sensor’s job is to listen for detonation (pinging) and let the ECU pull a bit of ignition timing to protect the engine. That means better longevity under load, smoother running with variable fuel quality, and fewer nasty rattles up hills with the family on board. On the 2001 Odyssey’s V6, the sensor is mounted on the engine block beneath the intake manifold in the V of the cylinders, so it’s not something you’ll spot at a glance under the bonnet.

This isn’t a routine replacement item, but it does deserve attention if you’re chasing a check‑engine light (often P0325), audible pinging, sluggish performance, or increased fuel use. Before swapping parts, it’s worth checking the basics: good fuel (91–95 RON in AU/NZ is fine for a healthy Odyssey), no vacuum leaks, solid engine grounds, and a clean, undamaged knock‑sensor sub‑harness. Oil or coolant contamination around the connector can also upset the signal.

When replacement is needed, plan for intake manifold removal to access the sensor comfortably. Use a quality OE‑spec sensor, follow the factory torque spec, and avoid thread sealants that can insulate the sensor from the block. After refit, clear codes, perform an idle relearn if required, and road‑test under light to moderate load to confirm the ECU is happy. Because the sensor is sensitive to how it couples to the block, overtightening or installing on a dirty mating surface can cause false readings.

• Common signs of trouble: check‑engine light with P0325, pinging under load, lack of power, rough acceleration, poorer economy.
• Good servicing habits: maintain healthy cooling and ignition systems, keep connectors clean and clipped, and use quality fuel.

Technical references: Honda Odyssey Service Manual 1999–2004 (PGM‑FI – Knock Sensor, DTC P0325), Honda Electronic Parts Catalogue (2001 Odyssey J35A1 – Knock Sensor), SAE J2012 DTC Definitions (P0325).

FAQs

Where is the knock sensor on a 2001 Honda Odyssey?
It sits on the engine block under the intake manifold, in the valley of the V6. Access typically requires removing the upper intake components for a clear path to the sensor and its connector.

What are the symptoms of a failing knock sensor?
Expect a check‑engine light (often P0325), possible pinging under load, dull performance, and sometimes increased fuel consumption. The ECU may run more conservative timing if it can’t trust the signal.

Is it okay to keep driving with a P0325 code?
It will usually run, but it’s not ideal. The ECU may pull timing as a safeguard, which can hurt performance and economy. If real detonation occurs and isn’t being managed, long‑term engine damage is possible, so it’s best to diagnose and fix it soon.