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Important: Verify connector shape and pins match your original part.
4-Piece Upstream & Downstream Lambda O2 Sensor
Fits BMW 325Ci 325i M56 Engine (2003-2006)
Replaces OE: 234-5134, 234-4473
Resolves Symptoms
- Check Engine Light (P0420/P0171)
- Rough Idle & Hesitation
- Poor Fuel Economy (MPG)
- Failed Emissions Inspection
Estimated Delivery
Free
Ordered
Oct 15
Prepared
Oct 15-Oct 16
Delivered
Oct 17-Oct 20
Dispatched quickly from local US warehouses.
2-Year Warranty
🛡️ Quality Coverage: Protects against any manufacturing defects for 2 full years.
🔄 Free Replacement: Brand-new replacement for free if quality issues occur.
30-Day Return & Refund
📦 Free Returns: Zero costs to you if the product has quality issues.
💰 Full Refunds: 100% money-back guarantee within 30 days for defective items.
5-Step Fitment Guide
- Check OE: Find original part no. & plug.
- Compare Photos: Match plug with our images.
- Verify YMM: Confirm via fitment tool.
- Review Specs: Check pins & dimensions.
- Purchase: Buy confidently once matched!
Review Rewards
Share an install photo & review to unlock:
- Under $50 Orders: 3% Off Next Order
- $50+ Orders: 5% Direct Cashback
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$95.95
-
No hidden fees: What you see is what you pay.
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Restore performance: Fix issues and drive with confidence.
Check Engine Light? Find Your Symptoms
🌬️ O2 & A/F Sensors
- P0134No Activity Detected
- P0135Heater Circuit Malfunction
- P0137/38Circuit Low/High Voltage
- P2195Signal Stuck Lean
- P0030/31Heater Control Circuit
⛽ Fuel & Air Mixture
- P0171/74System Too Lean
- P0172System Too Rich
- P2096Post-Catalyst Trim Too Lean
- P0087Fuel Rail Pressure Low
- P0201-04Injector Circuit Open
♻️ Catalytic Converters
- P0420Efficiency Below Threshold (B1)
- P0430Efficiency Below Threshold (B2)
⚡ Ignition / Misfires
- P0300Random Misfire
- P0301-06Cylinder-Specific Misfire
Automotive-Leader Sensors
Vehicle Compatible
|
Year
|
Make
|
Model
|
Engine/Displacement
|
Note
|
|---|---|---|---|---|
|
2003-2006
|
BMW
|
325Ci
|
2.5L L6
|
M56 Engine (M56B25, SULEV)
|
|
2003-2005
|
BMW
|
325i
|
2.5L L6
|
M56 Engine (M56B25, SULEV)
|
Product Specifications
Warranty & Support: 2 Years + Pre-sale Load Test + 24/7 Technical Support
|
Item
|
Specification
|
|---|---|
|
Core Part Number
|
234-5134
Interchange: 2345134, 234 5134, 11787515826, 11787515827, 11787529980, 11787530736 |
|
Position
|
Exhaust System, Upstream, Front, Pre-Catalytic Converter
|
|
Key Parameters
|
- Sensor Type: Heated
- Connector Gender: Male - Thread Diameter: 0.711 in - Wire Quantity: 5 Wires - Wire Harness Length: 40.67 in - Grade Type: Regular - Fit Type: Specific Fit |
|
Core Part Number
|
234-4473
Interchange: 2344473, 234 4473, 11787514926, 11787514927, 25658, 25024677, ES10914 |
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Position
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Exhaust System, Downstream, Rear, After Catalytic Converter on Downpipe
|
|
Key Parameters
|
- Sensor Type: Heated Oxygen Sensor
- Connector Gender: Male - Mounting Type: Threaded - Thread Diameter: 0.708 in - Wire Quantity: 4 Wires - Wire Harness Length: 38.58 in - Grade Type: Regular - Fit Type: Specific Fit |