MiniCatsSA
Stainless steel mini catalytic converter O₂ sensor spacer shown with its ceramic honeycomb catalyst element and perforated restrictor disc, M18 × 1.5 thread
In stock · Ships from Gauteng

Mini Catalytic Converter O₂ Sensor Spacer

Car Oxygen Sensor Adapter Spacer Adapter Bung Catalytic Converter Repair

R350.00 incl. VAT

● In stock — 100 available

  • ✓ Standard delivery R99 — 2 to 4 business days
  • ✓ Express delivery R149 — next business day
  • ✓ Guest checkout, no account needed
  • ✓ Card and instant EFT via PayFast

Specification

Thread sizeM18 × 1.5
Length58 mm
Diameter16 mm
MaterialStainless steel
Weight0.2 kg
Catalyst elementYes — miniature catalyst inside the body
Oxygen sensorNot included
In the box1 × mini catalytic converter O₂ sensor spacer

What it does

The MiniCat threads into the exhaust bung where your downstream oxygen sensor normally sits. The sensor then threads into the spacer, which holds it 58 mm further out of the direct exhaust stream, inside a small chamber containing a miniature catalyst element.

Because the sensor now samples a damped, delayed gas sample rather than the raw stream, its output trace flattens out. That is the pattern the ECU reads as a healthy catalytic converter, so the catalyst efficiency monitor stops setting P0420 or P0430.

Being straight about it: this changes what the sensor reports. It does not repair a catalytic converter and it does not reduce what comes out of your tailpipe. If your cat is genuinely intact and something else is setting the code, a spacer hides the symptom instead of fixing the cause — the P0420 guide walks through how to tell the difference before you spend anything.

What arrives

Mini catalytic converter oxygen sensor spacer, exploded view Exploded assembly drawing of the M18 x 1.5 stainless steel oxygen sensor spacer. It shows the 58 mm body in cross-section with its female bore and male thread, the ceramic honeycomb catalyst element and the seven-hole perforated restrictor disc that sit inside it, and the vehicle's own oxygen sensor, drawn as a dashed ghost because it is not supplied. What is in the box Exploded view — every part supplied, and the one part that is not. = where those parts sit inside the body 58 mm M18 × 1.5 Ceramic honeycomb catalyst sits inside the body chamber Perforated restrictor disc 7 drilled holes meter the gas sample Your existing O2 sensor NOT INCLUDED re-use the one already on your car Female M18 × 1.5 bore your O2 sensor screws in here Stainless steel body, sectioned Male M18 × 1.5 thread screws into the exhaust bung

The spacer body, the ceramic honeycomb catalyst element and the perforated restrictor disc. Your oxygen sensor is re-used and is not supplied.

Where it goes on the car

Where the oxygen sensor spacer fits Side view of a car exhaust line, running from the engine and manifold on the left through the downpipe, catalytic converter, mid-pipe and silencer to the tailpipe on the right. The spacer is fitted only at the downstream oxygen sensor position after the catalytic converter, never at the upstream sensor before it, and an inset detail shows the spacer threaded between the exhaust bung and the vehicle's own sensor. Where it fits Side view. Front of the car is at left; exhaust flows left to right. ENGINE Upstream sensor (pre-cat) Never fit it here your sensor (not supplied) the spacer The spacer fits HERE downstream (post-cat) sensor only manifold downpipe catalytic converter mid-pipe silencer tailpipe V6 and V8 engines have two banks and therefore two downstream sensors - they need two spacers. Detail: bung, spacer, your sensor 58 mm bung in pipe spacer your sensor 58 mm: sensor sits out of the gas stream

The spacer fits the downstream sensor only — the one after the catalytic converter. Fitting it upstream will cause running problems.

Frequently asked questions

What thread size is the MiniCat O₂ sensor spacer?

M18 × 1.5, which is the thread used by the large majority of oxygen sensors. Check your own sensor before ordering — the guide at /guides/will-it-fit shows how.

Does the oxygen sensor come with it?

No. You reuse your existing downstream oxygen sensor. The spacer threads into the exhaust bung, and the sensor then threads into the spacer.

Will this fix a P0420 code?

It addresses the code by changing what the downstream sensor reports, and it resolves many cases. It will not help if you have an exhaust leak, a failing oxygen sensor or a misfire — rule those out first.

Do I need one or two?

One per downstream oxygen sensor. Four-cylinder engines normally have one. V6 and V8 engines usually have two, one per bank, and need two spacers.

How long does delivery take in South Africa?

Standard delivery is R99 and takes 2 to 4 business days. Express is R149 for next business day. Orders ship from Johannesburg, Gauteng via The Courier Guy.

Customer reviews

★★★★★

Perfect

exactly as description

Taqi · November 2025

Legal notice. This part alters how your vehicle reports downstream oxygen sensor readings. Removing or bypassing a functioning catalytic converter on a road-going vehicle may affect its roadworthy status and emissions compliance in South Africa. Sold for motorsport, off-road and diagnostic use. It is the buyer's responsibility to confirm what is permitted for their vehicle and use case.