OEM Automotive Oxygen Sensor 28122177 For AvtoVAZ GAZ UAZ ZAZ

Technical Notes:

• This is a 4‑wire heated planar probe oxygen sensor. The planar design incorporates a thin, multi‑layer ceramic substrate, enabling the sensing element to reach operating temperature almost immediately after a cold start, allowing the ECU to enter closed‑loop fuel control sooner and significantly reduce cold‑start emissions.
• The sensor monitors the oxygen content in the exhaust gas and sends a voltage signal to the ECU. The ECU uses this feedback to continuously adjust fuel delivery, maintaining the optimal air‑fuel mixture for efficient combustion.
• The sensor is constructed with a stainless‑steel shell that provides excellent durability against rust and harsh exhaust environment conditions. The platinum coating on the ceramic element is applied using vapour deposition for even application, and a protective spinel coating helps prevent solid exhaust particles from damaging the component.
• As a regulating probe, this sensor is installed before the catalytic converter and directly influences the ECU’s fuel trim adjustments.
• All sensors are 100% tested to meet or exceed original equipment quality standards. The threads are factory pre‑greased to prevent seizing in the exhaust bung and to facilitate easier future removal.
• This is a direct‑fit replacement featuring a vehicle‑specific electrical connector and pre‑terminated wiring, eliminating the need for cutting or splicing during installation.

The following part numbers are known cross‑references for this Lambda Sensor. Always verify physical fitment (connector shape, cable length and thread size) with your original part before purchasing.

Cross-Reference Notes:

• The LADA / VAZ OE number 21074385001000 is a direct cross‑reference and is considered the primary OEM part number for this sensor in the LADA and VAZ ecosystems.
• The 4‑pin connector block 28122177 with 4 contacts is an integral component of the oxygen sensor used on vehicles such as VAZ 2108, 2110, and others.
• FACET 10.8357 is an OE‑equivalent aftermarket part that shares identical specifications: heated, planar probe, pre‑greased threads, 450 mm cable length, and 4‑circuit design.
• SIDAT 90074HQ is another aftermarket equivalent with planar probe design and 4‑conductor configuration.
• Always physically compare your old sensor‘s connector shape (4‑pin), pin count, cable length (approx. 450 mm), and thread size (M18 × 1.5) before purchasing, as aftermarket equivalents may have slight variations in connector design or calibration parameters.

This Lambda Sensor is an original equipment component widely used across the LADA (AvtoVAZ) model range, as well as other Eastern European vehicle manufacturers such as GAZ, UAZ, and ZAZ. The sensor is installed before the catalytic converter (upstream position) and is compatible with 1.4L – 1.7L 4‑cylinder petrol engines meeting EURO‑II and EURO‑III emissions standards. It serves as the primary regulating probe for air‑fuel mixture control.

Fitment Notes:

• This is an upstream (pre‑catalyst / front) oxygen sensor for the majority of applications listed above. It is installed before the catalytic converter and serves as the primary regulating probe for air‑fuel mixture control.
• The sensor is compatible with vehicles meeting EURO‑II and EURO‑III emissions standards equipped with fuel injection systems.
• Upstream and downstream O₂ sensors are not interchangeable in most vehicles. For vehicles equipped with two oxygen sensors (upstream regulating probe + downstream diagnostic probe for EURO‑IV and higher), this part is for the upstream position only. Replacing an upstream sensor with a downstream unit (or vice versa) will result in improper ECU readings and persistent fault codes.
• This OE number is confirmed as an Original Equipment (OEM) part for LADA models and is factory‑installed on the specified vehicles.
• Not compatible with diesel engines unless factory‑fitted with a lambda sensor system. Pre‑Euro‑4 diesel engines generally do not use oxygen sensors.
• The vehicle fitment information above is a guide only. Always confirm compatibility using your vehicle‘s VIN or by physically inspecting your old sensor‘s connector shape (4‑pin), cable length (approx. 450 mm), and thread size (M18 × 1.5) before purchasing.

• Engine compatibility summary:

  Engine Displacement	Engine Codes	Power Output
  1.4L 16V	—	approx. 70‑90 HP
  1.5L / 1.6L 8V / 16V	—	71‑136 HP
  1.7L	ZMZ‑409 (UAZ/GAZ)	approx. 90‑120 HP
  2.3L	ZMZ‑405 (GAZ)	approx. 140‑160 HP

A faulty lambda sensor directly affects the ECU‘s ability to accurately monitor the air‑fuel mixture. While the engine may still run, fuel economy, emissions, and OBD‑II readiness are all negatively affected. Replace your lambda sensor immediately if you experience any of the following symptoms.

Potential Causes of Sensor Failure:

• Normal wear and tear — Lambda sensors typically degrade after 60,000 – 100,000 miles (100,000 – 160,000 km) of operation due to continuous exposure to high‑temperature exhaust gases (up to 930 °C) and thermal cycling stress. The sensing element‘s response slows over time.
• Heater circuit failure — The internal heating element opens or shorts. This causes the sensor to respond extremely slowly or not at all when cold, triggering P0030‑P0037 codes and affecting cold‑start performance.
• Contamination (“sensor poisoning”) — Oil, coolant (head‑gasket leaks), silicone‑based sealants, or the use of leaded fuel permanently coats the ceramic sensing tip, destroying its ability to detect oxygen. Common sources include worn piston rings / valve seals (oil contamination) and the use of silicone sealants near the exhaust system during maintenance.
• Physical impact damage — Dropping the sensor (even from a low height) or impact from road debris can crack the fragile ceramic element.
• Wiring / connector issues — Damaged wiring, loose connections, corrosion at the connector, or an intermittent open / short circuit can trigger fault codes even when the sensor itself is healthy.
• Exhaust leaks upstream of the sensor — False oxygen readings from an upstream exhaust leak (cracked manifold, failed gasket, etc.) will cause erratic sensor output and may be incorrectly attributed to a faulty sensor.

Diagnostic Tips:

• A failing lambda sensor frequently triggers the MIL without any noticeable drivability change initially. Fuel consumption, however, is still negatively affected. Proactive replacement at the recommended interval can restore up to 15% of lost fuel efficiency.
• P0133 (O₂ Sensor Circuit Slow Response) is a common code for this type of sensor, indicating that the sensor‘s switching speed has fallen below the acceptable threshold. This affects the ECU‘s ability to maintain precise air‑fuel control.
• P0420 can be caused by a failing oxygen sensor, a failing catalytic converter, or an upstream sensor that is no longer providing accurate readings to the ECU. If both P0133 (upstream sensor issue) and P0420 (catalyst efficiency) appear together, the upstream sensor is likely the root cause.

• To diagnose a faulty sensor:

  • Heater circuit test: Use a digital multimeter to measure the resistance across the two heater circuit pins. A healthy sensor should read within the expected specification (consult your vehicle‘s service manual). An open circuit (infinite resistance) or short circuit (0 Ω) indicates heater failure.
  • Sensor signal test: Use an OBD‑II scanner or oscilloscope to monitor the sensor voltage output under steady‑state driving. A healthy narrow‑band upstream sensor fluctuates continuously between approximately 0.1 V – 0.9 V (typically oscillating several times per second). If the voltage remains steady (stuck high, stuck low, or at a fixed mid‑range value), does not fluctuate, or changes very slowly, the sensor is failing.
• Always investigate the root cause before replacing the sensor — if contamination (oil, coolant, silicone) caused the failure, replacing the sensor without addressing the underlying issue will result in repeated premature failure.

1. Confirm Fitment — Physical Inspection is Essential

• This is a direct‑fit upstream sensor with a 4‑pin connector, 450 mm cable length, M18 × 1.5 thread, and 22 mm (7/8″) spanner size.
• ⚠️ Do not purchase based solely on the OE number. Aftermarket equivalents may have slight differences in cable length, connector shape, or calibration parameters. If the connector does not match, do not install.
• Physically compare your original sensor‘s connector shape (4‑pin), pin count, cable length (approx. 450 mm), and thread size (M18 × 1.5) before ordering. The connector block is an integral element of the oxygen sensor.
• Measure the cable length of your original sensor. While the OE specification is 450 mm, aftermarket equivalents may vary. A significant mismatch may cause routing difficulties or the connector failing to reach the harness.
• As listed on various parts websites, this OE number (28122177) is applicable for LADA (AvtoVAZ) models. The OE numbers 21074385001000 and 21074‑3850010‑00 are direct factory references.

2. Verify Sensor Position — Upstream / Pre‑Catalyst Only

• This sensor is designed for the upstream (pre‑catalyst / front) position as a regulating probe (Bank 1, Sensor 1). It should be installed before the catalytic converter.
• Upstream and downstream O₂ sensors are not interchangeable in most vehicles. Replacing an upstream sensor with a downstream unit (or vice versa) will result in improper ECU readings, persistent fault codes, and the ECU may not be able to correctly monitor catalyst efficiency.
• For most 4‑cylinder LADA / VAZ vehicles meeting EURO‑II / EURO‑III standards, there is one oxygen sensor (upstream position). For newer EURO‑IV and above vehicles, there are two oxygen sensors: upstream (pre‑cat / regulating) and downstream (post‑cat / diagnostic). This part is for the upstream position only.
• How to verify: Locate your vehicle‘s catalytic converter. The upstream sensor is typically installed in the exhaust manifold or in the pipe immediately before the catalytic converter. If your faulty sensor is located after the converter, this part is not suitable for your application.

3. Replacement Interval

• Lambda sensors degrade gradually over time, often without triggering immediate fault codes. Their switching response becomes slower and their voltage range narrows with age and mileage.
• Replacement every 100,000 – 160,000 km (60,000 – 100,000 miles) is recommended to maintain optimal fuel efficiency, catalytic converter health, proper emissions output, and correct OBD‑II monitor readiness.
• Even if no Check Engine Light is present, an aged sensor will still respond more slowly than a new one, negatively affecting fuel economy and emissions. Proactive replacement can restore up to 15% of lost fuel efficiency.

4. Installation Tips

Before Installation:

• Allow the exhaust system to cool completely before removal — the exhaust manifold and catalytic converter remain dangerously hot for up to 30 minutes after engine shutdown. Attempting removal on a hot system risks severe burns.
• Disconnect the vehicle‘s battery negative (-) cable before starting work to prevent electrical issues, potential ECU damage, or accidental short circuits.
• Use a high‑quality O₂ sensor socket (22 mm / 7/8″) with an offset design to prevent stripping the sensor‘s flats and to provide better access in confined engine bays. A standard deep socket can easily damage the sensor housing or its flats.

Removal of the Old Sensor:

• Apply penetrating oil (e.g., WD‑40) to the threads of the old sensor the night before removal. This can significantly ease extraction, especially if the sensor has been installed for many years in the harsh exhaust environment.
• If the sensor is difficult to remove when cold, it may be easier when the exhaust is warm (run the engine for 1‑2 minutes, then allow it to cool until it is warm but not scalding). Exercise extreme caution to avoid burns — wear heavy‑duty heat‑resistant work gloves.
• Do not use excessive force — damage to the exhaust bung threads can result in expensive repairs, potentially requiring exhaust manifold replacement or thread repair (helicoil / timesert).
• Disconnect the electrical connector carefully — press the locking tab and pull only the connector housing (never pull directly on the wires). Follow the sensor wires to locate the connector, which is typically secured to a bracket on the engine block or valve cover.
• Inspect the old sensor‘s connector, cable, and tip for signs of contamination (oil, soot, coolant residue), melting, or cracking. Note any contamination — this indicates an underlying engine issue (e.g., oil consumption from worn piston rings or valve seals, coolant leak, or silicone contamination) that must be addressed before installing the new sensor to prevent repeat failure.

Installation of the New Sensor:

• Do not apply additional anti‑seize compound unless the new sensor‘s threads are completely dry. Most OE‑quality sensors come with factory pre‑greased threads. Adding extra anti‑seize can contaminate the sensor tip and cause premature failure. If the threads appear dry and no pre‑grease is evident, apply a small amount of sensor‑safe anti‑seize compound to the threads only — never to the sensor tip.
• Do not use silicone sealants anywhere near the exhaust system — silicone vapour will permanently contaminate and destroy the oxygen sensor (this is one of the most common causes of premature failure and is almost always non‑warrantable).
• Avoid touching the sensor tip — skin oils contain salts and contaminants that can damage the ceramic sensing element, causing inaccurate readings and premature failure. Always handle the sensor by the hexagon nut or connector body.
• Do not drop the sensor — the ceramic element inside the metal housing is brittle and can crack upon impact, rendering the sensor inoperative even if no external damage is visible.

• Tighten to the correct torque — typical torque for an M18 × 1.5 oxygen sensor is 40 – 50 Nm (30 – 37 ft‑lb) . Use a torque wrench to avoid overtightening or undertightening.

  • CAUTION: Overtightening can damage threads in the exhaust bung and may crack the sensor housing. Undertightening may cause exhaust leaks and false oxygen readings.
• Route the wiring harness securely using the original clips and routing guides to prevent contact with hot exhaust components (exhaust manifold, catalytic converter, EGR pipes) or moving parts (drive shafts, steering components, cooling fans). Use zip ties if original clips are missing or damaged, but ensure they are rated for high‑temperature engine bay use.
• Reconnect the electrical connector fully — an audible click confirms correct engagement. Ensure the locking tab is fully seated and locked into place.
• Reconnect the vehicle‘s battery after installation is complete.

Post‑Installation:

• Start the engine and allow it to reach normal operating temperature (closed‑loop mode). This typically takes 5‑10 minutes of driving or idling.
• Verify that no exhaust gas leakage exists around the sensor bung (listen for “puffing” sounds, or use a soap‑and‑water solution sprayed around the threads — bubbles indicate a leak).
• Use an OBD‑II scanner to clear any existing fault codes (old codes stored in the ECU must be cleared to turn off the MIL and reset monitors).
• Drive the vehicle through a complete drive cycle (typically 10‑20 minutes of mixed driving: stop‑start traffic, steady cruising at 50‑60 mph, moderate acceleration and deceleration) to allow the ECU to re‑learn adaptation values and complete oxygen sensor and catalyst monitors.
• After the drive cycle, re‑scan for fault codes to confirm that the oxygen sensor monitors have completed and that no new codes have appeared.

5. Required Tools

6. Quantity Needed — Upstream Sensor

• Most LADA / VAZ 4‑cylinder petrol engines meeting EURO‑II / EURO‑III standards have one oxygen sensor (upstream position). This part is the correct replacement.
• For newer vehicles (EURO‑IV and above) that have two oxygen sensors: upstream (pre‑cat / regulating) — this part, and downstream (post‑cat / diagnostic) — a different part number is required.
• If your vehicle is equipped with only one oxygen sensor (pre‑EURO‑III standards), this upstream sensor is the correct replacement.

7. Professional Installation Recommended

• While this is a direct‑fit part, professional installation is strongly recommended if you are not experienced with exhaust system work or if the sensor is located in a difficult‑to‑reach position (e.g., on the exhaust manifold between the engine and firewall, requiring special tools or access).
• After replacement, the ECU may need to have adaptation values reset using manufacturer‑specific diagnostic equipment.

• Improper installation can lead to:

  • Exhaust leaks around the sensor bung
  • Cross‑threaded or damaged exhaust bung threads — expensive to repair, possibly requiring manifold replacement
  • Sensor damage from contamination or mishandling (touching tip, dropping, silicone exposure)
  • Wiring damage from contact with hot exhaust components or moving parts
  • Persistent ECU fault codes despite a correctly functioning sensor
• If your vehicle is due for scheduled maintenance, consider having the oxygen sensor replaced alongside an exhaust system inspection, as exhaust leaks upstream can affect sensor readings.

8. Warranty

• Genuine OE‑manufactured sensors typically include a manufacturer warranty — commonly 12 months from the date of purchase. Aftermarket equivalents may offer varying warranty periods (commonly 1 to 2 years). Premium aftermarket sensors may carry extended warranties (e.g., 3‑year / 60,000‑mile coverage). Check with your specific retailer for their warranty terms and return policy.
• Important: Most warranties are voided if the sensor tip shows contamination from improper handling (e.g., touching the tip, dropping the sensor, silicone exposure, or installation with contaminated hands or tools). Oxygen sensors are often non‑returnable except for approved warranty replacement due to contamination risk.
• Keep your original packaging until the new sensor is installed and confirmed working — you may need it for warranty claims or returns.

9. Common Mistakes to Avoid

Disclaimer: While we strive for accuracy, vehicle specifications and OE part numbers may vary by production date, market region, and vehicle trim level. This part number (28122177) is a 4‑wire heated upstream (pre‑catalyst) oxygen sensor, widely used across LADA (AvtoVAZ), GAZ, UAZ, and ZAZ 4‑cylinder petrol engines. You must verify physical fitment (4‑pin connector, approx. 450 mm cable length, M18 × 1.5 thread) and confirm the position (upstream / pre‑catalyst) of your old sensor before purchasing. This sensor is compatible with vehicles meeting EURO‑II and EURO‑III emissions standards and is not compatible with diesel engines unless factory‑fitted (pre‑Euro‑4 diesel engines generally do not use lambda sensors). The OE numbers 21074385001000 and 21074‑3850010‑00 are the primary factory references for this sensor in the LADA / VAZ ecosystem. If your vehicle is not listed above, or if you are unsure of compatibility, consult your vehicle‘s manufacturer specifications, an authorised dealer, or a qualified mechanic before ordering.