O2 Oxygen Sensor Upstream Downstream for Toyota Tacoma (2005-2012) 2.7L

Direct-Fit O2 Sensor Kit for 2005-2012 Toyota Tacoma (N200)

What it Does: This matched upstream and downstream oxygen sensor kit restores closed-loop fuel trim control and emissions monitoring on the 2005-2012 Toyota Tacoma (N200) equipped with the 2TR-FE 2.7L engine.

The Stock Toyota Tacoma Sensor Failure

Over extended thermal cycling on the N200 chassis with the 2TR-FE 2.7L I4, OEM oxygen sensors suffer heater element burnout, carbon fouling, and zirconia ceramic degradation. As the upstream air-fuel ratio sensor slows, the ECM loses accurate closed-loop fuel control and defaults to rich mapping. Meanwhile, a fatigued downstream sensor triggers P0420 catalyst efficiency alerts alongside P0031, P0136, and P2195 fault codes.

Common Symptoms of a Failing OEM O2 Sensor

• Check Engine Light / DTCs: Active P0031, P0136, P2195, or P0420 codes from heater circuit failure or sluggish voltage switching.
• Rough Idle & Hesitation: Delayed wideband feedback causes erratic fuel trims, throttle stumble, and fouled spark plugs.
• Poor Fuel Economy & Failed Emissions: Rich default mapping drops MPG and pushes tailpipe hydrocarbons past legal limits.

The Direct-Fit Zirconia & AFR Sensor Solution

Replacing both sensors as a matched pair restores factory ECM voltage signaling using direct-fit units for 234-9008 (upstream) and 234-4622 (downstream) positions. Each sensor combines a laser-welded stainless steel body, breathable PTFE filter, and high-purity zirconia sensing element built to resist continuous exhaust heat soak. Pre-terminated OEM connectors eliminate wire splicing and achieve rapid light-off temperatures for precise closed-loop stoichiometry.

What's Included

• 1 Upstream Oxygen Sensor
• 1 Downstream Oxygen Sensor

Technical Specifications

Compatibility

• 2005-2012 Toyota Tacoma 2.7L (1 Upstream Air-Fuel Ratio Sensor & 1 Downstream Oxygen Sensor)

Frequently Asked Questions & Fitment Warnings

Does this fit the N200 Tacoma?

Yes. Direct fit for 2005-2012 Tacoma N200 with the 2TR-FE 2.7L engine. Excludes 4.0L V6 models; confirm engine before ordering.

Will this clear P0031, P0136, or P0420 codes?

Yes, if sensor wear caused the fault. Replacing 234-9008 and 234-4622 clears heater and response codes; persistent P0420 indicates converter wear.

Are factory connectors attached for plug-and-play installation?

Yes. Both sensors include OEM connectors for zero-splice installation; apply O2-safe anti-seize strictly to threads before torquing.

The Toyota Heavy-Duty Standard

Built for Tacoma trucks facing towing loads and sustained exhaust heat. Matched sensing keeps your 2TR-FE 2.7L running clean, efficient, and CEL-free.