Which cylinder is number 1 on a Honda?

On most Honda automobiles, cylinder number 1 is at the end of the engine where the timing belt/chain and accessory drive are located; on transverse inline‑four models (Civic, Accord 4‑cyl, CR‑V, etc.) this typically places cylinder 1 on the passenger side in North American left‑hand‑drive vehicles, numbered 1‑2‑3‑4 across the engine. On Honda’s transverse V6 (J‑series in Accord V6, Odyssey, Pilot, Ridgeline), cylinder 1 is on the rear (firewall) bank at the passenger‑side end. For most Honda multi‑cylinder motorcycles, cylinder 1 is the leftmost cylinder as you sit on the bike. This article explains how to identify cylinder 1 across common Honda layouts and how to verify it on your specific model.

How Honda numbers cylinders in common layouts

Transverse inline‑four (Civic, Accord 4‑cyl, CR‑V, HR‑V, Fit, Element, etc.)

Honda’s inline‑four engines (D‑, B‑, K‑, R‑, L‑series, including modern “Earth Dreams” 1.5T and 2.0T) use the timing belt/chain end as the reference for cylinder 1. In front‑wheel‑drive transverse installations common in North America, that end is typically on the passenger side of the engine bay.

Result: cylinder numbering runs 1‑2‑3‑4 from the timing belt/chain end across to the opposite end (usually toward the driver side in LHD markets). This holds whether the engine is belt‑driven or chain‑driven and regardless of intake/exhaust orientation.

Longitudinal inline‑four (S2000, select specialty applications)

In longitudinal installations, the timing end faces the front of the vehicle. Cylinder 1 is therefore at the front of the engine, nearest the radiator/front bumper, and numbering proceeds 1‑2‑3‑4 toward the firewall.

Transverse V6 (Honda J‑series: Accord V6, Odyssey, Pilot, Ridgeline; Acura MDX/TL/CL of the same family)

Honda’s transverse V6s number cylinders by bank, with Bank 1 defined as the bank containing cylinder 1. On J‑series engines, Bank 1 is the rear bank closest to the firewall.

Facing the vehicle from the front:
– Rear bank (firewall side) holds cylinders 1‑2‑3, running roughly from passenger side to driver side.
– Front bank (radiator side) holds cylinders 4‑5‑6, again passenger to driver.
Thus, cylinder 1 is at the rear, passenger‑side corner of the engine bay in left‑hand‑drive North American models.

Honda motorcycles (general conventions)

For most Honda multi‑cylinder motorcycles (inline‑four and parallel‑twin), cylinder 1 is defined as the leftmost cylinder when seated on the motorcycle (clutch‑lever side). Numbering then proceeds left‑to‑right as the rider sits on the bike. V‑engine and boxer layouts can differ; always check the model‑specific service manual.

Quick reference by model family

The following list summarizes where you’ll typically find cylinder 1 on popular Honda models. Use it as a starting point before verifying on your specific vehicle.

• Civic/CR‑V/Accord 4‑cyl/HR‑V/Fit/Element (transverse inline‑4): Cylinder 1 at the timing belt/chain end, typically passenger side in North American LHD vehicles; numbered 1‑2‑3‑4 across the engine.
• Accord V6/Odyssey/Pilot/Ridgeline (J‑series transverse V6): Cylinder 1 on the rear (firewall) bank, passenger‑side end; rear bank is cylinders 1‑2‑3, front bank is 4‑5‑6.
• S2000 (longitudinal inline‑4): Cylinder 1 at the front of the engine, nearest the radiator/front bumper; numbering runs front to rear.
• Most Honda inline‑four motorcycles (CB/CBR/NC/CB500 families): Cylinder 1 is the leftmost as you sit on the bike; numbering left to right.

These conventions cover the vast majority of Hondas on the road; exceptions are rare but can occur with unusual engine orientations or specific motorcycle V/boxer layouts.

How to verify cylinder 1 on your specific Honda

If you want to be absolutely certain for tune‑ups, ignition diagnosis, or emissions troubleshooting, use the steps below to confirm cylinder numbering on your exact engine.

1. Locate the timing belt/chain end: On cars, find the end with the cam belt/chain cover or accessory drive pulleys. That end marks cylinder 1 on inline engines.
2. Identify banks on V6 engines: The bank nearest the firewall is Bank 1 on J‑series; cylinder 1 resides on that rear bank, passenger‑side end (LHD).
3. Check coil/plug wire labels and casting marks: Many Honda coil packs and valve covers have subtle numbering or stamped casting marks near plug wells.
4. Consult the factory service manual (FSM): It includes a cylinder numbering diagram; PDFs are available for most models via Honda/Acura service sites or reputable manual publishers.
5. Use OBD clues if needed: Bank 1 oxygen sensors and catalytic converters are on the bank containing cylinder 1; parts diagrams and scanner data can help confirm bank orientation.

Verifying with documentation prevents misrouting plug wires, swapping injectors during diagnostics, or misinterpreting misfire and O2 sensor codes.

Common mistakes to avoid

Misidentifying cylinder 1 can lead to persistent misfires, incorrect part replacement, and failed emissions repairs. Keep the following pitfalls in mind.

• Assuming “frontmost” equals cylinder 1 on all engines: True on longitudinal inline engines, but not on transverse layouts where the timing end may be to one side.
• Confusing Bank 1/Bank 2 on V6s: On Honda J‑series, Bank 1 is the rear (firewall) bank—opposite of what some generic diagrams show.
• Using driver/passenger sides without market context: “Passenger side” here refers to North American left‑hand‑drive vehicles; in right‑hand‑drive markets the physical side may be opposite.
• Applying car conventions to motorcycles: Many bikes use rider‑left as #1, but V/boxer layouts can differ; always check the model manual.

A quick check of the timing end or the official diagram eliminates these common errors and saves troubleshooting time.

Summary

For most Hondas, cylinder 1 is anchored to the timing belt/chain end of the engine. That places it at the passenger‑side end on transverse inline‑four cars in North America and on the rear (firewall) bank, passenger‑side end on J‑series transverse V6s. On most Honda multi‑cylinder motorcycles, cylinder 1 is the leftmost as you sit on the bike. When in doubt, verify with the factory service manual or by identifying Bank 1 components.

Which cylinder is number 1 Honda?

On an inline engine: the number one cylinder is located at the front of the engine, closest to the timing cover. On a V type engine: one cylinder head is slightly forward of the other, toward the front of the engine. Cylinder number one is the forward most cylinder in that bank.

Which is cylinder 1 on a V6?

On a V6 engine, cylinder #1 is typically the forward-most cylinder on the passenger side (also known as Bank 1). The other cylinders in that bank are numbered sequentially (2, 3) towards the back of the engine, while the other bank (Bank 2, driver’s side) follows the same pattern: #4 is the forward-most cylinder, followed by #5 and #6.

Where is the cylinder 1 on a Honda Fit?

Looking at the engine under the hood, cylinder 1 is left, closest to the ‘front’ of the engine.

How can you tell which is cylinder 1?

To identify cylinder number one in an engine, especially on an inline engine, it’s usually the one closest to the front of the engine, often near the timing chain/belt or accessory drive belts. For V-type engines, it’s generally the one closest to the crankshaft on the front-most bank. If you’re still unsure, consult your vehicle’s manual for specific details. 
This video explains how to identify cylinders on a GM 5.3L engine: 58sBarbour’s Auto HelpYouTube · Dec 11, 2023
Here’s a more detailed breakdown:
Inline Engines:

• Front-most Cylinder: In inline engines (where cylinders are arranged in a single row), cylinder number one is typically located at the front of the engine.
• Timing Components: This is often where you’ll find the timing chain or belt cover, as well as the accessory drive belts and pulleys. 

V-Type Engines:

• Crankshaft Side: For V-type engines (where cylinders are arranged in two banks), cylinder number one is usually the one closest to the crankshaft on the front-most bank. 
• Bank Designation: The bank containing cylinder number one is often designated as “Bank 1” for diagnostic purposes. 

Other Indicators:

• Firing Order: Cylinder number one is the first cylinder in the engine’s firing order. 
• Vehicle Manual: The most reliable way to determine cylinder number one is to consult your vehicle’s manual, which will have specific details for your engine’s make and model.