🔧 Oxygen Sensors - Replacement

Your CR-V uses an upstream air/fuel ratio sensor and a downstream oxygen sensor. Replacing both restores fuel control and catalyst monitoring if the sensors are slow, aged, or setting heater/signal codes.

Difficulty Level: Intermediate | Estimated Time: 1.5-2.5 hours

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⚠️ Safety & Precautions

• Let the exhaust cool fully before starting. The exhaust and sensors get very hot.
• Disconnect the negative battery cable if you will be working near wiring connectors for a long time.
• Do not twist the sensor wiring. Unplug the connector before loosening the sensor.
• Use jack stands if you raise the vehicle. Never work under a vehicle supported only by a jack.
• Use penetrating oil on stubborn threads.

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🔧 Required Tools

You'll need the following tools for this repair:

• 22mm oxygen sensor socket
• 3/8-inch ratchet
• 3/8-inch breaker bar
• Torque wrench
• Penetrating oil
• Flat trim tool
• Gloves
• Safety glasses
• Jack stands
• Floor jack
• Wheel chocks

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Upstream air/fuel ratio sensor - Qty: 1
• Downstream oxygen sensor - Qty: 1

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📋 Before You Begin

• Park on level ground and set the parking brake.
• Let the exhaust cool completely.
• If the vehicle has been run recently, wait until the catalytic converter and exhaust pipes are safe to touch.
• If you disconnect the battery, you may need to reset radio and window settings afterward.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Access the sensors

• Open the hood for the upstream sensor.
• Raise the front of the vehicle with a floor jack and support it with jack stands for the downstream sensor.
• Use wheel chocks at the rear wheels.

Step 2: Disconnect the upstream sensor

• Locate the upstream air/fuel ratio sensor on the exhaust stream ahead of the catalytic converter.
• Use a flat trim tool to release any harness clips if needed.
• Unplug the electrical connector by pressing the lock tab and separating the connector.
• Unplug first, then loosen the sensor.

Step 3: Remove the upstream sensor

• Spray penetrating oil on the sensor threads if they are rusted.
• Use a 22mm oxygen sensor socket and 3/8-inch breaker bar to loosen the sensor.
• Remove the sensor by hand once it breaks free.
• Install the new upstream sensor by hand first to avoid cross-threading.
• Use a torque wrench to tighten the sensor to 33 Nm (24 ft-lbs).

Step 4: Reconnect the upstream sensor

• Route the wire exactly like the original so it will not touch the exhaust.
• Reconnect the electrical connector until it clicks.
• Reinstall any harness clips with the trim tool.

Step 5: Remove the downstream sensor

• Go under the vehicle and locate the downstream oxygen sensor behind the catalytic converter.
• Disconnect the sensor connector first.
• Spray penetrating oil on the threads if needed.
• Use a 22mm oxygen sensor socket, 3/8-inch ratchet, and breaker bar to remove the sensor.
• Install the new downstream sensor by hand first.
• Use a torque wrench to tighten the sensor to 33 Nm (24 ft-lbs).

Step 6: Reconnect the downstream sensor

• Route the harness away from the exhaust and moving parts.
• Reconnect the connector until it locks.
• Make sure the wire clips are secure.

Step 7: Reassemble and lower the vehicle

• Check both sensor wires for proper routing and clearance.
• Lower the vehicle carefully from the jack stands.
• Remove the wheel chocks.

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✅ After Repair

• Start the engine and let it idle.
• Check for exhaust leaks or warning lights.
• If the check engine light was on, clear codes with a scan tool.
• Road test the vehicle and confirm no new codes return.

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💰 DIY vs Shop Cost

Shop Cost: $350-$700 (parts + labor)

DIY Cost: $140-$320 (parts only)

You Save: $210-$380 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.5-2.5 hours.

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🎯 Ready to get started?

HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.