2003–2006 Hyundai Elantra
Save $230 by doing it yourself! Shop cost: $400
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| Part Name | Part Number | Price | Buy |
|---|---|---|---|
| Upstream Oxygen Sensor | 234-9006 | $80.00 | |
| Downstream Oxygen Sensor | 234-9007 | $90.00 |
About prices: shown prices are estimates from typical Amazon listings and change frequently, and cheaper alternatives may be available. Confirm the current price on Amazon before buying.
💡 Pro tip: Order all parts at once to save on shipping
Follow these steps carefully
Confirm whether you are replacing an upstream (pre-cat) or downstream (post-cat) sensor and match the part to that location on the 2003-2009 Hyundai Elantra. Work only on a cool exhaust. Wear gloves and eye protection; raise and support the 2003-2009 Hyundai Elantra if underbody access is required.
On the 2003-2009 Hyundai Elantra: trace the sensor pigtail to its connector — often clipped to the frame, valve cover, or transmission tunnel. Unplug it and free any harness clips so the lead can rotate with the sensor during removal.
On the 2003-2009 Hyundai Elantra: use an oxygen-sensor socket or appropriate wrench. Apply penetrating oil if seized and allow it to soak; heat carefully only if needed and safe. Turn the sensor out — avoid damaging nearby wires, heat shields, or catalytic-converter threads.
On the 2003-2009 Hyundai Elantra: compare thread pitch and connector to the old unit. Most new sensors include anti-seize on the threads — do not get anti-seize on the tip or protection tube. Never clean or paint the sensing element.
On the 2003-2009 Hyundai Elantra: thread the new sensor by hand to avoid cross-threading, then torque to the specification (often around 30–40 N·m — use the value for this vehicle). Route the pigtail away from hot exhaust and moving parts, and reconnect the connector until it locks.
Lower the 2003-2009 Hyundai Elantra if raised. Start the engine and confirm the heater circuit runs with no immediate exhaust leak at the bung. Clear related codes with a scan tool and road-test; monitors may need a complete drive cycle before readiness returns.
Test your repair before closing everything up. If something doesn't work right, double-check your steps.
⚠️ Common Mistakes to Avoid
2011–2016
2011–2016
2011–2016
2017–2020
2003–2006
2003–2006