Walker Products 250-21012 oxygen sensor for the 1991-1994 Mercury Capri 4-cylinder 1.6L and other vehicles sends the engine computer a reading of the oxygen in the exhaust gas. This Walker Products oxygen sensor is made for its own application and fitment position, so the ECU gets the diagnostic feedback it expects.
- Measures exhaust oxygen to monitor the air-fuel ratio and help fine-tune the mixture for combustion efficiency
- Electrodes made of a gas-permeable platinum layer
- Coating guards the electrode surfaces against contamination and erosion from combustion residue and particulates
- Monitors exhaust gases to help reduce pollutants
Quick facts
- Part: Walker Products 250-21012 oxygen sensor
- Fits: 1991-1994 Mercury Capri 4-cylinder 1.6L and other vehicles
- Position: Upstream
- Condition: New
A failing sensor can show up as an engine that runs poorly, higher fuel consumption or a lit malfunction indicator light, and each of those can have other causes. Before replacing anything, look over the sensor, its wiring harness and its connector for physical damage with the engine off and cool; a shop can read any stored fault codes.
Fits
The upstream position takes a single sensor, and this listing is one sensor. The fitment also includes the 1983-1987 Mazda 626 4-cylinder 2.0L, the 1988-1989 626 4-cylinder 2.2L and the 1989 Ford Probe 4-cylinder 2.2L. If your car is not named here, open the "Vehicles it fits" section and check your exact model and engine.
Specifications
Fit and size
- Position: Upstream
- Quantity per application: 1
- Thread: M18 - 1.5
Build and materials
- Type: narrow-band, direct fit
- Electrodes: gas-permeable platinum layer
- Condition: New
Frequently Asked Questions
Is this a Probe oxygen sensor for the 1989 Ford Probe 4-cylinder 2.2L?
Yes. Walker Products 250-21012 fits the 1989 Ford Probe 4-cylinder 2.2L, where the upstream position takes one sensor.
Is this a Mazda 626 oxygen sensor for the 1983-1987 model with the 4-cylinder 2.0L?
Yes. It fits the 1983-1987 Mazda 626 4-cylinder 2.0L and the 1988-1989 626 4-cylinder 2.2L. Open the "Vehicles it fits" section to check your exact engine.
Is the Walker Products 250-21012 a narrow-band or wideband sensor?
Walker Products 250-21012 is a narrow-band, direct-fit oxygen sensor for the upstream position. It reads the oxygen content of the exhaust gas to monitor the air-fuel ratio.
What are the electrodes on this upstream oxygen sensor made of?
The electrodes are made of a gas-permeable platinum layer. A coating protects those electrode surfaces from contamination and erosion by combustion residue and particulates.
Will a bad upstream oxygen sensor set a fault code?
Newer vehicles store fault codes in the ECU, and some relate to the affected sensor and its systems. A shop can read them to help find the cause.
