Where is the oxygen sensor located on a 2008 Honda Accord?

There are two oxygen sensors on the four‑cylinder 2008 Accord (one upstream, before the catalytic converter, and one downstream, after it). The V6 version uses three sensors (two upstream, one downstream).

In more detail, oxygen sensors monitor exhaust gases to help the engine manage fuel mixture and emissions. Their exact placement can vary slightly by trim and exhaust layout, but the upstream sensors are always before the catalytic converter and the downstream sensor is after it. This guide outlines where to look on common configurations for the 2008 Accord.

Four‑cylinder engine: where to find the two sensors

For the four‑cylinder engine, locate these two sensors along the exhaust pipe:

• Upstream sensor (pre‑cat): threaded into the exhaust pipe just after the exhaust manifold, before the catalytic converter. It is typically accessible from beneath the vehicle on the driver’s side.


• Downstream sensor (post‑cat): threaded into the exhaust pipe after the catalytic converter. This sensor is usually located closer to the front of the car or along the section of pipe after the cat, and is accessible from underneath as well.

These two sensors provide the primary feedback for catalytic converter efficiency and fuel trim for the engine in four‑cylinder models.

V6 engine: where to find the three sensors

For the V6 engine, there are three sensors in typical configurations:

• Upstream sensor 1 (pre‑cat, bank 1): mounted on the exhaust manifold to pre‑cat pipe for the first bank (usually the left bank when facing the engine).


• Upstream sensor 2 (pre‑cat, bank 2): mounted on the exhaust manifold to pre‑cat pipe for the second bank (the opposite side).


• Downstream sensor (post‑cat): mounted after the catalytic converter on the exhaust pipe, monitoring the exhaust after treatment.

As with the four‑cylinder setup, the exact positions can vary with trim level or exhaust routing, but the pattern is two upstream sensors (one per bank) and a single downstream sensor after the cat.

Tips for locating and servicing

When you’re trying to locate or replace an O2 sensor, keep these notes in mind:

• Engine should be cool before attempting any work to avoid burns or damage to sensor threads.


• Work from underneath the car and use proper lifting supports if you need to crawl under the exhaust system.


• O2 sensors are threaded into exhaust piping and can seize over time; applying a penetrating oil and using a 22mm (or OEM‑specific) sensor socket can help.


• After replacement, clear codes with a scan tool and perform a drive cycle to verify proper operation.

If you’re unsure about which sensor corresponds to your exact trim or if you suspect a faulty sensor, consulting the official Honda service manual or a qualified technician can prevent misidentification and damage.

Summary

The 2008 Honda Accord places two O2 sensors on the four‑cylinder version — one before and one after the catalytic converter. The V6 version uses three sensors — two upstream (one for each bank) and one downstream after the cat. Location varies slightly by trim, but the upstream sensors are always before the catalytic converter and the downstream sensor is after it. Follow proper safety steps and use the right tools when inspecting or replacing them.

Where are the O2 sensors located on a 2008 Honda Accord?

Itself is really easy to remove. So the tab to remove this is actually back here. So push that tab down and then I can pull this off. So see how that's pulled through the back.

What are the symptoms of a bad O2 sensor on a Honda Accord?

A well-working O2 sensor can be an important component of a consistent running car. Still, a bad O2 sensor can probably lead to bad smells from your car, poor gasoline efficiency, and a below-level running engine.

How many O2 sensors does a 2008 Honda Accord V6 have?

4
Fit Vehicles:

How much does it cost to replace the oxygen sensor on a 2008 Honda Accord?

The average cost for a Honda Accord Oxygen Sensor Replacement is between $462 and $518. Labor costs are estimated between $54 and $79 while parts are priced between $408 and $439. This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.