Subaru EJ20 Firing Order and Cylinder Numbering Diagram
Subaru EJ20 firing order 1-3-2-4 with boxer cylinder numbering, bank layout, ignition verification, and misfire troubleshooting.
The Subaru EJ-series boxer-four firing order is 1-3-2-4. Cylinders 1 and 3 share one bank; cylinders 2 and 4 share the opposite bank.
The Subaru EJ-series boxer-four firing order is 1-3-2-4. Cylinders 1 and 3 share one bank; cylinders 2 and 4 share the opposite bank. A firing order is the sequence in which the cylinders begin their power strokes. It is not the same thing as cylinder numbering, distributor-cap clock position, or ignition-coil connector order. Confusing those references can create a no-start, violent backfire, dead cylinders, or a diagnostic trail that looks like a fuel or mechanical problem.
Use the verified order only after identifying the engine family and camshaft. Classic engines can accept camshaft swaps that change the required sequence, while modern coil-on-plug engines have no distributor cap to route. The table, bank diagram, and procedure below keep those concepts separate and show how to confirm No. 1 on compression before moving any wires.
Interactive Subaru EJ20 Boxer Four firing-order diagram
Branded downloads includedPNG and PDF exports carry the TorqueSheet logo, torquesheet.com, source-page URL, and republishing attribution request. The PDF source link is clickable.
Select each cylinder to walk through the firing order. Cylinder-bank numbering and distributor direction must match the identified engine family.
Subaru Ej20 Firing Order
| APPLICATION / ITEM | SPECIFICATION | NOTES |
|---|---|---|
| EJ20 firing order | 1-3-2-4 | Mechanical combustion sequence |
| Bank with cylinders 1 and 3 | 1 front, 3 rear | Viewed in installed vehicle orientation |
| Opposite bank | 2 front, 4 rear | Do not number straight across |
EJ20 versions span distributor, wasted-spark, and coil-on-plug systems, so connector and lead routing must match the exact engine management system.
Which EJ20 Boxer Four firing order applies?
All four cylinders lie horizontally, so the bank diagram is more useful than an inline sketch. This distinction matters because the engine can look nearly identical from above. Treat the camshaft or engine assembly as the authority when parts have been mixed. A firing order cast into an intake, copied from a generic decal, or remembered from another V8 is not enough to identify a modified engine.
The application table separates the order, cylinder banks, and ignition-system notes. Read all columns before routing. The first number in 1-3-2-4 is cylinder 1, but the physical No. 1 terminal can appear in different clock positions when a distributor has been installed on a different gear tooth.
Bank numbering and verification on the EJ20 Boxer Four
The firing order stays mechanical while the external ignition layout changes among EJ20 versions.
EJ20 versions span distributor, wasted-spark, and coil-on-plug systems, so connector and lead routing must match the exact engine management system.
Subaru EJ20 Boxer Four specifications can change by model year, engine, platform, wheel, and installed component. Confirm the VIN or engine identity, part numbers, fastener condition, and the current manufacturer instructions before service.
Procedures used with this specification
These steps are the same for every vehicle in this family, so they are documented once rather than repeated on each page. The values above remain specific to this Subaru EJ20 Boxer Four.
Subaru EJ20 Firing Order and Cylinder Numbering Diagram FAQs
What is the subaru ej20 firing order?+
The Subaru EJ-series boxer-four firing order is 1-3-2-4. Cylinders 1 and 3 share one bank; cylinders 2 and 4 share the opposite bank.
Technical sources
TorqueSheet favors engine- and component-specific manufacturer instructions over unsourced universal values.
1Subaru technical specifications — horizontally opposed enginePrimary Subaru technical table documenting the boxer-four 1-3-2-4 firing order.↗