Parts for your 2018 Toyota Camry-Oxygen sensor

2018 Toyota Camry oxygen sensor (A/F and O2)

Based on Toyota’s 2018 Camry (XV70) Repair Manual and Electronic Parts Catalogue, the vehicle is fitted with exhaust oxygen sensing as standard. The 2.5L A25A-FKS and hybrid A25A-FXS engines use an upstream air–fuel ratio (A/F) sensor and a downstream heated oxygen sensor (HO2S). The 3.5L V6 2GR-FKS uses one A/F sensor and one HO2S per bank. Toyota’s service literature covers diagnostics and DTCs such as P2195/P2196 (A/F sensor) and P0136/P0137/P0156 (HO2S), confirming their role in fuel control and catalyst monitoring.

On a 2018 Camry, the upstream A/F sensor continuously measures oxygen content to let the ECU trim fuelling on the fly, helping the car sip petrol, run smoothly and meet emissions targets. The downstream HO2S checks how well the catalytic converter is doing its job. Together, they keep the mix spot on under Aussie and Kiwi driving—city commutes, long open-road runs and everything in between.

While Toyota doesn’t set a strict replacement interval, these sensors are wear items. Many workshops see the upstream A/F sensor tiring around 120,000–180,000 km, with the downstream HO2S often lasting similar or a touch longer. Tell-tales include higher fuel use, a rougher idle, a whiff of sulphur, or a check engine lamp with the codes above. Hybrids still rely on these sensors whenever the petrol engine is running, so the same advice applies.

Good servicing habits help the 2018 Camry’s oxygen sensors live a long life:

• Fix any oil, coolant or exhaust leaks quickly—contaminants and false air will foul sensors.
• Avoid silicone sealants that aren’t O2-sensor safe, vapours can poison elements.
• When replacing, use quality OEM-spec parts (often Denso for Toyota), the right O2 socket and the specified torque. Some new sensors come pre-coated—don’t add extra anti-seize unless instructed.
• Inspect and route wiring away from heat, damaged looms cause intermittent faults.
• After fitting, clear codes, perform an ECU relearn/drive cycle and verify fuel trims and sensor response on a scan tool.

How many are fitted? The 2.5L four-cylinder and the hybrid typically have two (Bank 1 Sensor 1 A/F, Bank 1 Sensor 2 HO2S). The V6 has four (one A/F and one HO2S per bank). If the bonnet’s up and a spanner’s out, it pays to diagnose properly before swapping parts—wideband A/F sensors are quick thinkers but can be misread without live data.

Popular questions about 2018 Toyota Camry oxygen sensors

How many oxygen sensors are in a 2018 Toyota Camry?

The 2.5L four-cylinder and the hybrid have two sensors: an upstream air–fuel ratio (A/F) sensor and a downstream heated oxygen sensor (HO2S). The 3.5L V6 has four—one A/F and one HO2S on each bank. This layout supports precise fuel control and catalyst monitoring.

Sensor 1 (upstream) handles fuelling, while Sensor 2 (downstream) checks catalyst efficiency. Bank numbering depends on engine type, but the principle stays the same.

When should the oxygen sensor be replaced on a 2018 Camry?

There’s no fixed kilometre interval from Toyota, replacement is usually triggered by fault codes, poor fuel economy, or sluggish sensor readings. Many techs see upstream sensors fade around 120,000–180,000 km in local conditions.

If you see codes like P2195/P2196 (A/F) or P0136/P0137 (HO2S), inspect for leaks and wiring faults first, then replace the affected sensor with an OEM-spec unit.

Can a DIYer replace the oxygen sensor at home?

Yes, with care. Use an O2 sensor socket, penetrating oil on cold threads, and observe torque specs. Work on a cooled exhaust to avoid burns, and don’t twist the harness. After installation, clear codes and complete a drive cycle to confirm trims and readiness.

If the sensor is seized or wiring is heat-baked, it’s wise to let a workshop handle it to avoid damaged threads or connectors.