Parts for your 2020 Mazda 3-Egr valve

2020 Mazda 3 EGR valve — whether it’s there, and when it matters

For most 2020 Mazda 3 models sold in Australia and New Zealand, an external EGR valve isn’t fitted or required. The common Skyactiv-G 2.0 and 2.5 petrol engines in the BP-series Mazda 3 control residual exhaust gas using variable valve timing (internal EGR) and rely on a three-way catalytic converter for NOx control, so there’s no standalone EGR valve to service. This is reflected in Mazda’s BP Workshop Manual for SKYACTIV-G 2.0/2.5 (Fuel and Emission Control sections) and Mazda’s electronic parts catalogues for the BP chassis, which list no EGR valve assembly for these petrol variants. Mazda’s 2020 AU/NZ specification guides also show the petrol Mazda 3 meeting emissions without external EGR hardware.

The outlier is the Skyactiv-X X20 (SPCCI) variant, which was offered in limited numbers in AU/NZ during 2020. Skyactiv-X does use an electronically controlled, cooled EGR circuit as part of its lean-burn strategy. Mazda’s technical material and SAE publications on SPCCI note the role of cooled EGR in stabilising combustion and reducing pumping losses, so an EGR valve is indeed present on X20 models.

Why don’t the mainstream Skyactiv-G 2.0/2.5 BP cars use an external EGR valve? With a stoichiometric air–fuel ratio, a high-efficiency three-way catalyst, a 4–2–1 exhaust manifold and Dual S-VT (variable valve timing) creating internal EGR via valve overlap, the engine controls NOx and knock without the complexity of an external EGR valve and cooler. That’s one less emissions component under the bonnet to fail or maintain, and it helps keep servicing simple and costs down for owners of 2020 Mazda 3 G20/G25 models.

Owners of the Skyactiv-X X20 should note that their vehicle does have an EGR valve and cooler. Good quality fuel, regular oil changes, and following Mazda’s scheduled servicing help keep deposits in check. If drivability issues occur (rough idle, hesitation, or an emissions warning), a technician will typically check for EGR flow or performance faults and may inspect the EGR valve and cooler for restriction before cleaning or replacement as required—using factory procedures and updated calibration where applicable.

Technical sources referenced: Mazda BP-series Workshop Manual (2019–2021, SKYACTIV-G Fuel and Emission Control, SKYACTIV-X SPCCI system overview), Mazda Electronic Parts Catalogue for BP Mazda 3, Mazda Australia and New Zealand 2020 model specification guides, and Mazda/SAE technical papers describing SPCCI and cooled EGR in Skyactiv-X.

• No external EGR valve on 2020 Mazda 3 Skyactiv-G 2.0/2.5 (AU/NZ market).
• External, cooled EGR valve fitted on 2020 Mazda 3 Skyactiv-X X20.

Tip: Unsure which engine is fitted? The build plate and owner’s manual will indicate “Skyactiv-X” for X20 models, mainstream G20/G25 petrol cars are Skyactiv-G and don’t have an external EGR valve.

Popular questions

Does a 2020 Mazda 3 have an EGR valve?
Most AU/NZ 2020 Mazda 3 models with the Skyactiv-G 2.0 or 2.5 petrol engine don’t have an external EGR valve. The exception is the Skyactiv-X X20, which does use a cooled EGR valve as part of its SPCCI combustion system.

How can someone tell if their 2020 Mazda 3 is the Skyactiv-X (and has an EGR valve)?
Look for “Skyactiv-X” badging, X20/X20 Astina trim in documents, or check the owner’s manual and build plate. If it’s Skyactiv-G (G20/G25), there won’t be an external EGR valve. If it’s Skyactiv-X, there will be.

What are signs of EGR issues on a Skyactiv-X X20?
Symptoms can include rough idle, hesitation on light throttle, higher fuel use, or an engine/emissions warning. A workshop will typically scan for EGR-related fault codes and inspect the EGR valve and cooler for restriction before cleaning or replacing parts using Mazda procedures.