Catalyst codes, spacers and what actually works
Everything below is written to be useful even if you decide not to buy anything. If a spacer is the wrong answer for your car, these guides say so.
P0420 Code: What It Means and How to Fix It
P0420 means catalyst efficiency below threshold on Bank 1. Here is what sets the code, every real cause ranked, and how to fix it without wasting money.
Read the guide →P0430 Code: Bank 2 Catalyst Efficiency Explained
P0430 is catalyst efficiency below threshold on Bank 2. Learn how to identify Bank 2 on your V6 or V8, diagnose the right side, and what two banks means.
Read the guide →How to Install an O₂ Sensor Spacer
Step-by-step guide to fitting a mini catalytic converter O₂ sensor spacer to the downstream oxygen sensor, including torque, wiring and the drive cycle.
Read the guide →Will an O₂ Sensor Spacer Fit My Car?
How to check whether an M18 × 1.5 O₂ sensor spacer fits your car: confirm the sensor thread, measure clearance for 58 mm, check wire length and sensor count.
Read the guide →O₂ Sensor Spacer vs a New Catalytic Converter
O₂ sensor spacer vs a new catalytic converter: what each one actually does, cost and fitting time compared, and how to pick the right fix for a P0420.
Read the guide →Check Engine Light After a Decat: What Now?
Check engine light after a decat, straight pipe or downpipe? Why the P0420 appears, what it does to fuelling, and the four ways to deal with it, ranked.
Read the guide →Buying a Mini Catalytic Converter Spacer in South Africa
How to buy an O₂ sensor spacer in South Africa: thread size, stainless vs mild steel, catalyst element or hollow, import vs local, pricing and delivery.
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