SENSOR DE OXÍGENO (SONDA LAMBDA)

<style> .qf-wrap{font-family:Arial,sans-serif;color:#222;max-width:960px;margin:0 auto} .qf-block{margin-bottom:10px} .b-section{border:1px solid #e0e0e0;border-radius:4px;overflow:hidden} .b-header{background:#1e2025;color:#fff;padding:14px 18px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;user-select:none} .b-title{font-size:15px;font-weight:bold;letter-spacing:.3px} .b-chevron{font-size:12px;transition:transform .25s;transform:rotate(180deg)} .b-chevron.open{transform:rotate(0deg)} .b-body{padding:20px 22px;display:none;background:#fff} .b-body.open{display:block} .qf-intro{font-size:14px;line-height:1.7;color:#333;margin-bottom:14px} .qf-symptom{border-left:4px solid #c0392b;padding:8px 14px;margin:7px 0;background:#fafafa;font-size:14px} .qf-obd-grid{display:flex;flex-wrap:wrap;gap:10px;margin-top:14px} .qf-obd-card{border-left:4px solid #c0392b;background:#fafafa;padding:10px 14px;min-width:200px;flex:1 1 200px} .qf-obd-code{font-weight:bold;font-size:14px;color:#c0392b} .qf-obd-desc{font-size:13px;color:#444;margin-top:3px} .qf-table{width:100%;border-collapse:collapse;font-size:13px;margin-top:10px} .qf-table th{background:#1e2025;color:#fff;padding:9px 12px;text-align:left} .qf-table td{padding:8px 12px;border-bottom:1px solid #e0e0e0;vertical-align:top} .qf-table tr:nth-child(even) td{background:#fafafa} .qf-log-grid{display:flex;flex-wrap:wrap;gap:12px} .qf-log-item{background:#fafafa;border:1px solid #e0e0e0;border-radius:4px;padding:12px 16px;flex:1 1 180px} .qf-log-label{font-size:11px;color:#888;text-transform:uppercase;letter-spacing:.5px} .qf-log-value{font-size:14px;font-weight:bold;color:#222;margin-top:4px} .qf-steps ol{padding-left:20px;margin:0} .qf-steps li{padding:7px 0;font-size:14px;line-height:1.6;border-bottom:1px solid #f0f0f0} .qf-steps li:last-child{border-bottom:none} .qf-faq-item{margin-bottom:16px} .qf-faq-q{font-weight:bold;color:#1e2025;font-size:14px;margin-bottom:5px} .qf-faq-a{font-size:13px;color:#444;line-height:1.6} .qf-note{font-size:12px;color:#666;background:#fafafa;border:1px solid #e0e0e0;border-radius:3px;padding:8px 12px;margin-top:12px} .qf-disclaimer{font-size:12px;color:#888;margin-top:14px;border-top:1px solid #e0e0e0;padding-top:10px} </style> <div class="qf-wrap"> <!-- BLOCK 1: Overview --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('ov')"> <div class="b-title">Overview &amp; Operating Principle</div> <div class="b-chevron open" id="qf-chevron-ov">&#9650;</div> </div> <div class="b-body open" id="qf-body-ov"> <p class="qf-intro">The <strong>Honda Air/Fuel Ratio (AFR) Sensor</strong> &#8212; OEM reference 36531RB0003 &#8212; is a <strong>wideband upstream (pre-catalyst, Sensor 1) oxygen sensor</strong> used across a range of compact Honda and Acura petrol models from the mid-2000s through the mid-2010s. It replaces the earlier narrow-band switch-type sensors used on older Honda engines, delivering a continuous, linear signal across a wide lambda range (approximately &#955; 0.7&#8211;1.3 / AFR 10&#8211;19:1) rather than a simple rich/lean toggle.</p> <p class="qf-intro">Internally the sensor combines a <strong>Nernst cell</strong> (measurement element) with a <strong>pump cell</strong> that actively moves oxygen ions in or out of a sealed reference cavity to maintain stoichiometric conditions. The pump current required to sustain this balance is the linear AFR signal transmitted to Honda&#8217;s PGM-FI engine management system. An integrated ceramic heater (the two heater wires in the 4-pin connector) brings the tip to operating temperature (approximately 750&#8211;850&#176;C) within 20&#8211;30 seconds of a cold start, enabling immediate closed-loop fuel control and reducing cold-start emissions.</p> <p class="qf-intro">The PGM-FI ECU uses the upstream AFR sensor signal as the <strong>primary closed-loop fuel correction input</strong>, calculating short-term and long-term fuel trims. It also feeds the onboard OBD-II catalyst efficiency monitor (the downstream sensor compares against this reference). Accurate upstream AFR data is therefore essential for fuel economy, emissions, and the longevity of the catalytic converter.</p> <p class="qf-intro"><strong>Connector:</strong> 4-wire plug-in (2 heater wires, 1 signal current wire, 1 signal ground). <strong>Thread:</strong> M18 x 1.5. <strong>Wire harness length:</strong> approximately 485 mm. <strong>Net weight:</strong> 0.1 kg.</p> </div> </div> </div> <!-- BLOCK 2: Symptoms & Diagnostics --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('sym')"> <div class="b-title">Symptoms &amp; Diagnostics</div> <div class="b-chevron open" id="qf-chevron-sym">&#9650;</div> </div> <div class="b-body open" id="qf-body-sym"> <p style="font-size:14px;color:#555;margin-bottom:12px;">A failing upstream AFR sensor on Honda Fit, Civic, Accord, CR-Z, Insight, CR-V, or Acura ILX/TSX typically presents with the following:</p> <div class="qf-symptom">Malfunction Indicator Lamp (MIL / Check Engine) illuminated &#8212; often the first and only early warning before driveability degradation becomes noticeable.</div> <div class="qf-symptom">Increased fuel consumption &#8212; without accurate AFR feedback, PGM-FI reverts to open-loop operation using fixed fuel maps, which are less efficient than closed-loop control.</div> <div class="qf-symptom">Rough or unstable idle &#8212; incorrect fuel trim corrections cause mixture instability at low load and light throttle conditions.</div> <div class="qf-symptom">Hesitation or stumble on light-throttle acceleration &#8212; the AFR sensor contributes most actively at partial throttle, so degradation is most evident in this range.</div> <div class="qf-symptom">Rich-running condition &#8212; if the sensor drifts lean or fails open, PGM-FI adds excessive fuel. Signs include black soot at the exhaust outlet and a fuel odour in the exhaust.</div> <div class="qf-symptom">Failed emissions inspection &#8212; uncontrolled fuel trims lead to elevated HC and CO levels that exceed test thresholds.</div> <div class="qf-symptom">Premature catalytic converter failure &#8212; chronic over-fuelling caused by a failed AFR sensor thermal-shocks and poisons the catalyst, triggering P0420 even after the sensor is replaced.</div> <div class="qf-symptom">Heater circuit failure &#8212; the heater wires are the most common failure point on high-mileage sensors. Heater failure causes prolonged open-loop operation especially on short cold-weather trips.</div> <div class="qf-obd-grid"> <div class="qf-obd-card"> <div class="qf-obd-code">P2195 / P2196</div> <div class="qf-obd-desc">O2 Sensor Signal Stuck Lean / Stuck Rich (Sensor 1) &#8212; primary diagnostic codes for a failed or drifted upstream AFR sensor on PGM-FI systems. Indicates the sensor output has lost dynamic range.</div> </div> <div class="qf-obd-card"> <div class="qf-obd-code">P0031 / P0032</div> <div class="qf-obd-desc">HO2S Heater Control Circuit Low / High (Sensor 1) &#8212; heater element open circuit or short to power/ground. Sensor may still report plausible values until element fails completely.</div> </div> <div class="qf-obd-card"> <div class="qf-obd-code">P0133</div> <div class="qf-obd-desc">O2 Sensor Circuit Slow Response (Sensor 1) &#8212; the sensor response time exceeds the OBD-II threshold, indicating element contamination or aging. Often the earliest stored DTC before a hard failure.</div> </div> <div class="qf-obd-card"> <div class="qf-obd-code">P0171 / P0172</div> <div class="qf-obd-desc">System Too Lean / Too Rich (Bank 1) &#8212; long-term fuel trim codes that result from sustained incorrect AFR sensor signal. Also triggered by intake leaks or MAF issues; inspect all sources before replacing the sensor.</div> </div> <div class="qf-obd-card"> <div class="qf-obd-code">P0420</div> <div class="qf-obd-desc">Catalyst System Efficiency Below Threshold &#8212; can result from a failed upstream AFR sensor causing chronic rich/lean excursions that damage the catalyst. Inspect the catalyst if this code appears alongside AFR sensor codes.</div> </div> </div> <div class="qf-note">Honda-specific tip: on PGM-FI vehicles, live AFR sensor health can be monitored via OBD-II scan data as the &#8220;Air Fuel Sensor (AFS) Current&#8221; or &#8220;B1S1 Pump Current&#8221; parameter. A healthy sensor shows dynamic, continuously varying readings that track throttle inputs. A fixed or slowly drifting reading indicates contamination or element failure before a DTC is stored.</div> </div> </div> </div> <!-- BLOCK 3: Logistics & Customs --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('log')"> <div class="b-title">Logistics &amp; Customs</div> <div class="b-chevron open" id="qf-chevron-log">&#9650;</div> </div> <div class="b-body open" id="qf-body-log"> <div class="qf-log-grid"> <div class="qf-log-item"> <div class="qf-log-label">International HS Code</div> <div class="qf-log-value">9026.80</div> </div> <div class="qf-log-item"> <div class="qf-log-label">EAEU Customs Code (TN VED)</div> <div class="qf-log-value">9026 80 200 0</div> </div> <div class="qf-log-item"> <div class="qf-log-label">Net Weight</div> <div class="qf-log-value">0.1 kg</div> </div> <div class="qf-log-item"> <div class="qf-log-label">Country of Manufacture</div> <div class="qf-log-value">China</div> </div> <div class="qf-log-item"> <div class="qf-log-label">Brand / SKU</div> <div class="qf-log-value">QF18A00029</div> </div> <div class="qf-log-item"> <div class="qf-log-label">Production Time</div> <div class="qf-log-value">32 days</div> </div> <div class="qf-log-item"> <div class="qf-log-label">MOQ</div> <div class="qf-log-value">50 pcs</div> </div> </div> <div class="qf-note">HS 9026.80 covers instruments for measuring or checking variables of liquids or gases (other than flow, level, pressure). Ceramic and zirconia element sensors may attract specific import duties in certain destination countries &#8212; confirm the applicable 10-digit subheading with your customs broker prior to importation.</div> </div> </div> </div> <!-- BLOCK 4: Vehicle Compatibility --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('compat')"> <div class="b-title">Vehicle Compatibility</div> <div class="b-chevron open" id="qf-chevron-compat">&#9650;</div> </div> <div class="b-body open" id="qf-body-compat"> <p style="font-size:13px;color:#666;margin-bottom:12px;">All entries are based on verified OEM cross-reference data. This is the <strong>upstream (pre-catalyst, Sensor 1)</strong> Air/Fuel Ratio sensor. Always verify the part number against your existing sensor before ordering &#8212; sensor position and connector type must match exactly. The downstream sensor uses a different part number and is not interchangeable with this unit.</p> <table class="qf-table"> <thead> <tr><th>Brand</th><th>Model</th><th>Engine</th><th>Years</th><th>Key OEM Ref.</th></tr> </thead> <tbody> <tr><td>Honda</td><td>Fit / Jazz (GD3 / GE)</td><td>1.5L L4 (L15A / L15B)</td><td>2007&#8211;2010</td><td>36531RB0003</td></tr> <tr><td>Honda</td><td>Fit / Jazz (GE6 / GE8)</td><td>1.5L L4 (L15A)</td><td>2011&#8211;2014</td><td>36531RE0003</td></tr> <tr><td>Honda</td><td>Civic (FB)</td><td>1.5L L4 (LDA3) / 2.4L L4 (K24Z7)</td><td>2012&#8211;2015</td><td>36531RE0003</td></tr> <tr><td>Honda</td><td>Accord (CP / CU)</td><td>2.4L L4 (K24Z3)</td><td>2008&#8211;2012</td><td>36531R40A01</td></tr> <tr><td>Honda</td><td>CR-V (RE)</td><td>2.4L L4 (K24Z1 / K24Z4)</td><td>2010&#8211;2011</td><td>36531R40A01</td></tr> <tr><td>Honda</td><td>CR-Z (ZF1 / ZF2)</td><td>1.5L L4 Hybrid (LEA1)</td><td>2011</td><td>36531RTW003</td></tr> <tr><td>Honda</td><td>CR-Z (ZF1 / ZF2)</td><td>1.5L L4 Hybrid (LEA1)</td><td>2012&#8211;2016</td><td>36531RE0003</td></tr> <tr><td>Honda</td><td>Insight (ZE2)</td><td>1.3L L4 Hybrid (LDA2)</td><td>2010</td><td>36531RBJ003</td></tr> <tr><td>Honda</td><td>Insight (ZE2)</td><td>1.3L L4 Hybrid (LDA2)</td><td>2010&#8211;2014</td><td>36531RE0003</td></tr> <tr><td>Acura</td><td>TSX (CU2)</td><td>2.4L L4 (K24Z3)</td><td>2009&#8211;2014</td><td>36531R40A01</td></tr> <tr><td>Acura</td><td>ILX (DE2)</td><td>2.0L L4 (R20A3) / 2.4L L4 (K24Z7)</td><td>2013&#8211;2014</td><td>36531RE0003</td></tr> </tbody> </table> <div class="qf-disclaimer">Based on OEM cross-reference numbers verified via Delcoribo, NGK/NTK 25680 cross-reference data, Honda OEM parts databases (hondafactoryparts.com, oempartsonline.com), and multiple aftermarket fitment sources. Position: upstream / pre-catalyst / Sensor 1. Always verify part number against original sensor before ordering.</div> </div> </div> </div> <!-- BLOCK 5: Installation Tips --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('inst')"> <div class="b-title">Installation Tips</div> <div class="b-chevron open" id="qf-chevron-inst">&#9650;</div> </div> <div class="b-body open" id="qf-body-inst"> <div class="qf-steps"> <ol> <li><strong>Confirm the sensor position before ordering.</strong> This is the upstream AFR sensor (pre-catalyst, Sensor 1). On the Honda Fit L15A engine, the upstream sensor is threaded directly into the exhaust manifold; on the Accord/CR-V K24 engines it is mounted in the front exhaust pipe before the catalytic converter. The downstream sensor (post-catalyst, Sensor 2) uses a different part number &#8212; never substitute positions.</li> <li><strong>Access on Honda Fit (GD/GE): the upstream sensor is in a tight location</strong> between the exhaust manifold, firewall, and engine block. On 2009+ Fit models, the connector is routed between the cylinder head and the firewall. Disconnect the connector first &#8212; it has a locking tab that must be pressed before the plug separates. Apply penetrating spray (PB Blaster or equivalent) to the sensor base 15&#8211;30 minutes before removal if the car has over 60,000 km on the original sensor.</li> <li><strong>Work on a warm or cold engine, not a hot one.</strong> A warm engine (driven 10&#8211;15 minutes, then allowed to cool 20 minutes) is ideal: expanded exhaust threads break free more easily, but the exhaust components are safe to handle. If the engine is fully cold, soak the sensor threads with penetrating spray. Avoid working on a fully hot exhaust &#8212; thermal expansion on aluminium manifolds can seize the sensor in place.</li> <li><strong>Use a 22 mm (7/8 in) oxygen sensor socket with a wire-pass slot.</strong> A standard 22 mm socket will pinch and damage the harness. On Fit models, access from above the engine bay is typically easier than from below due to underbody shielding. Use a flex-head ratchet or a universal joint extension for clearance in the tight space around the exhaust manifold.</li> <li><strong>Inspect the bung threads before installation.</strong> Clean with a thread chaser (M18 x 1.5) or a small wire brush if corrosion is present. Damaged bung threads will cause exhaust leaks and affect sensor accuracy after installation.</li> <li><strong>Check the new sensor for pre-coated threads</strong> (factory anti-seize). If threads are pre-coated (silver-grey paste on the thread flank), do not add additional anti-seize &#8212; double coating can cause over-torque conditions. If threads are bare, apply a thin coat of nickel-based anti-seize compound to the thread flanks only &#8212; avoid the first 1&#8211;2 threads at the sensor tip and keep anti-seize away from the ceramic element.</li> <li><strong>Thread in by hand for the first 3&#8211;4 turns</strong> to confirm no cross-threading. Torque to <strong>44 Nm (33 ft-lb)</strong> &#8212; Honda&#8217;s specified torque for M18 x 1.5 exhaust sensor bungs. Do not exceed this value; the ceramic element can crack under over-torque, causing an immediate failure of the new sensor.</li> <li><strong>Reconnect the 4-pin connector until the locking tab clicks.</strong> On Honda Fit models, route the wiring harness in exactly the same path as the original and re-secure all factory clips and brackets. The harness must be clear of the exhaust manifold heat shield and any moving components.</li> <li><strong>Clear stored DTCs</strong> with an OBD-II scanner. Start the engine and allow it to reach full operating temperature (approximately 5&#8211;10 minutes at idle). Verify live AFR sensor data shows dynamic variation tracking throttle inputs. Perform a short road test and recheck for stored codes before returning the vehicle to service.</li> </ol> </div> <div class="qf-note"><strong>Tools required:</strong> 22 mm (7/8 in) O2 sensor socket with wire-pass slot, flex-head or standard 3/8&#8243; drive ratchet, torque wrench (0&#8211;60 Nm range), universal joint extension (recommended for Fit/Insight), penetrating spray, OBD-II scanner.</div> </div> </div> </div> <!-- BLOCK 6: FAQ --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('faq')"> <div class="b-title">Frequently Asked Questions</div> <div class="b-chevron open" id="qf-chevron-faq">&#9650;</div> </div> <div class="b-body open" id="qf-body-faq"> <div class="qf-faq-item"> <div class="qf-faq-q">Do all six OEM numbers (36531RB0003, 36531RE0003, 36531R40A01, 36531RBJ003, 36531RE1Z01, 36531RTW003) use the same sensor body?</div> <div class="qf-faq-a">They are all upstream AFR sensors sharing the same sensing element and M18 x 1.5 thread, but they differ in harness length, connector routing, and bracket configuration to suit different engine bays. The 36531RB0003 is specific to Honda Fit 2009&#8211;2010; the 36531R40A01 is calibrated for the 2.4L K24 engine used in Accord, CR-V, and Acura TSX; the 36531RE0003 covers a wider range of later Civic/Fit/CR-Z/Insight applications. Always use the number that matches your original sensor for a direct plug-and-play fit &#8212; using a cross-reference with a different harness length may prevent the connector from reaching.</div> </div> <div class="qf-faq-item"> <div class="qf-faq-q">Is this sensor compatible with Honda diesel or full electric models?</div> <div class="qf-faq-a">No. Honda diesel engines use a different sensor family incompatible with this part. Full electric Honda/Acura vehicles (e.g. Honda e, Acura ZDX EV) do not have an internal combustion exhaust system and do not use oxygen sensors. Hybrid applications &#8212; specifically the Honda Insight ZE2 and CR-Z ZF1/ZF2 &#8212; are confirmed compatible as these use petrol engines with conventional exhaust and PGM-FI fuel management.</div> </div> <div class="qf-faq-item"> <div class="qf-faq-q">Does the PGM-FI ECU require reset or adaptation after fitting a new AFR sensor?</div> <div class="qf-faq-a">No reprogramming is needed. After installation, clear any stored DTCs with an OBD-II scanner, then drive through a complete drive cycle (cold start, varied throttle, highway and city operation). The PGM-FI system will automatically relearn short-term and long-term fuel trims within one to two drive cycles. If fuel trim codes (P0171 / P0172) return after the new sensor is fitted, inspect for intake air leaks, a dirty MAF sensor, or injector issues as these can cause fuel trim codes independently of sensor condition.</div> </div> <div class="qf-faq-item"> <div class="qf-faq-q">The upstream sensor on my Honda Fit is extremely difficult to access &#8212; is there a tip to make removal easier?</div> <div class="qf-faq-a">Honda Fit owners consistently report the upstream sensor as one of the more challenging DIY jobs on this platform due to its position between the exhaust manifold and firewall. The most effective approaches: soak the sensor base with penetrating oil the night before; use a flex-head ratchet with a short extension rather than a straight ratchet; approach from above (through the engine bay) rather than from below, as the underfloor shielding limits access on the GE series; and if the sensor is seized, apply heat to the bung area with a propane torch before attempting removal. On the 2009+ models the electrical connector sits between the cylinder head and firewall &#8212; disconnect this before attempting to remove the sensor body.</div> </div> <div class="qf-faq-item"> <div class="qf-faq-q">Is white-label or custom packaging available for wholesale orders?</div> <div class="qf-faq-a">Yes. ok.parts sources directly from the factory and can accommodate neutral/white-label packaging or custom-branded boxes with your logo and part numbering system. The standard MOQ for this item is 50 pieces; custom packaging may carry additional lead time beyond the standard 32 production days. Submit your specifications and branding requirements via the inquiry form for pricing and confirmation.</div> </div> </div> </div> </div> <!-- BLOCK 7: Frequently Replaced Together --> <div class="qf-block"> <div class="b-section"> <div class="b-header" onclick="qfToggle('rel')"> <div class="b-title">Frequently Replaced Together</div> <div class="b-chevron open" id="qf-chevron-rel">&#9650;</div> </div> <div class="b-body open" id="qf-body-rel"> <table class="qf-table"> <thead> <tr><th>Part</th><th>Reason for Combined Replacement</th></tr> </thead> <tbody> <tr> <td><strong>Downstream O2 Sensor (Sensor 2, post-catalyst)</strong><br><span style="font-size:12px;color:#666">e.g. Honda 36532RB0003 / Denso 234-4671</span></td> <td>Both sensors age in the same exhaust environment. When the upstream AFR sensor fails from element contamination or heater degradation, the downstream sensor is usually at a similar point in its service life. Replacing both during one workshop visit avoids a repeat job within months and ensures P0420 catalyst monitoring is accurate after the upstream sensor is renewed.</td> </tr> <tr> <td><strong>Catalytic Converter</strong><br><span style="font-size:12px;color:#666">e.g. Eastern 30424 / Walker 16499 for L15A Fit</span></td> <td>A failed upstream AFR sensor that causes prolonged rich running can overheat and chemically poison the catalyst substrate. If P0420 (catalyst efficiency) is stored alongside AFR sensor codes, inspect the catalyst before assuming the sensor is the only fault. Replacing only the sensor while the catalyst is damaged will result in P0420 returning within a short time.</td> </tr> <tr> <td><strong>MAF / MAP Sensor</strong><br><span style="font-size:12px;color:#666">e.g. Honda 37980RB0003 MAP sensor for L15A Fit</span></td> <td>P0171/P0172 fuel trim codes that appear alongside AFR sensor faults can also originate from a contaminated MAP or MAF sensor. Both sensors contribute to the fuel trim calculation; inspecting them simultaneously prevents misdiagnosis and a return visit after replacing only one component.</td> </tr> <tr> <td><strong>Spark Plugs</strong><br><span style="font-size:12px;color:#666">e.g. NGK IZFR6K-11 / Denso SK20HR11 for L15A</span></td> <td>Chronic rich operation caused by a degraded AFR sensor fouls spark plugs and deposits carbon on electrode tips. On high-mileage Honda Fit and Civic engines, a spark plug replacement alongside the AFR sensor service restores complete combustion performance and avoids rough-idle complaints after the new sensor has restored closed-loop operation.</td> </tr> <tr> <td><strong>Engine Air Filter</strong><br><span style="font-size:12px;color:#666">e.g. Honda 17220RB0505 / K&amp;N 33-2435 for Fit GE</span></td> <td>A blocked air filter enriches the mixture, accelerating contamination of the upstream AFR sensor&#8217;s ceramic element. Renewing the air filter at the same service interval removes a direct cause of premature degradation on the replacement sensor.</td> </tr> </tbody> </table> </div> </div> </div> </div> <script> function qfToggle(id){ document.getElementById('qf-body-'+id).classList.toggle('open'); document.getElementById('qf-chevron-'+id).classList.toggle('open'); } </script>