Firing order refers to the ignition sequence for the cylinders in an engine block.
When one cylinder is firing, an opposing cylinder is on the intake stroke such that there is a balance of forces on the crankshaft.
If all cylinders were to fire simultaneously, there would be uneven power output and breaking of the crankshaft. In addition, if a cylinder fails to fire, the engine misfires.
It’s usually a result of incomplete or no combustion. It feels like the engine is shaking as the car runs.
Other elements that the firing order affects include vibration and sound that the engine produces.
How Are Engine Cylinders Numbered
Generally, most manufacturers number the cylinders from the front to the rear of the engine.
However, this can also depend on the type of engine. For example, a straight engine’s numbering differs from a V engine and a radial engine.
Straight Engines
Straight engine cylinders are aligned in one row. They can either be four, six or eight-cylinder configurations.
The cylinders are numbered using the front of the engine as the base of numbering to the rear.
Radial Engines
In this type of engine, the cylinders are arranged like the spokes of a wheel. They are placed from a central crankcase.
As the name suggests, the cylinders are numbered in a circular format. The first cylinder is usually the one at the top. Each bank has an odd number of cylinders to allow for a good firing order.
You will find this engine configuration in aircraft engines.
V Engines
These engines contain two cylinder banks. The banks have an equal number of cylinders and are connected to a crankshaft. The two banks are also arranged at an angle that forms a V shape, hence the engine’s name.
When it comes to numbering in a V engine, there are two ways. For example, using the V6 engine as an example, the numbering on V engines is as follows;
- Numbering sequentially along the two banks. For example, 1-2-3 on one bank and 4-5-6 on the other bank.
- Numbering based on the position on the crankshaft. For example, 1-3-5 along one bank and 2–4-6 along the other, so the numbering is from front to back.
This type of engine powers the Honda Odyssey. Discussed below is the vehicle’s engine firing order.
Firing Order in Honda Odyssey
Firing order depends on the number of cylinders and the engine’s design. So to understand the Honda Odyssey firing order, you need to know what kind of engine the vehicle runs on.
The Japanese automaker Honda has made several improvements to the Odyssey engine since its inception in 1995. As a result, the Honda Odyssey has also used different cylinder configurations through its five generations.
Let’s look at the firing order in the Honda Odyssey over its generations.
First Generation (1995–1998)
The first generation’s engine configuration was either a 2.2 or a 2.3L four-cylinder engine.
The 2.2L had a power output of 140 horsepower, while the 2.3L had a power output of 150 horsepower. They were both mated to a 4-speed transmission.
However, since the engine was a four-cylinder, the crankpins were 90 degrees apart for both the 2.2 and 2.3L engines.
The firing order of the cylinders for this engine is 1-3-4-2, and the distributor rotation is clockwise.
Second Generation (1999 – 2004)
Honda upgraded their engine with this generation to a more powerful 3.5L V6 engine. In addition, it had a 4-speed transmission.
The result was a 210 horsepower engine which was very decent for a minivan. However, a 240-horsepower engine with a 5-speed transmission debuted in 2002.
The firing order for this 3.5L V6 is 1-4-2-5-3-6 with an ignition system with no distribution rotation system.
Third Generation (2005 – 2010)
This generation retained the 3.5L V6 engine of the previous generation mated to a 5-speed automatic transmission. It had a slightly higher horsepower of 244.
In this generation, Honda introduced a way to increase the vehicle’s fuel efficiency; the Hondas’s i-VTEC Variable Cylinder Management System. (VCM) This generation had four trim levels; the LX, EX, EX_L and the Touring.
The EX and Touring trims are the ones that got Honda’s VCM. This meant the vehicle could run on either three, four or all six cylinders depending on the driving conditions.
The Firing order for this generation depended on Hondas VCM. But since it’s a V6 engine, the firing order, when all cylinders are in use, is 1-4-2-5-3-6.
Fourth Generation (2011 – 2017)
The 3.5L V6 engine was still in use in this generation with a 5-speed automatic transmission.
However, some trim levels had the 6-speed automatic transmission. The power output for this generation was 248 horsepower.
This generation of Honda Odyssey’s also had cylinder deactivation as standard, and the firing order depended on this system.
The firing order when all the six cylinders are in use is 1-4-2-5-3-6.
Fifth Generation (2018 – Present)
This is the current generation of Honda Odyssey. It has the same 3.5L V6 engine with more power of up to 280 horsepower. Mated to this engine is either a 9 or 10-speed automatic transmission.
The firing order for this generation is the same as that of the previous generation, considering Hondas VCM. But when all six cylinders are in use, the firing order is 1–4-2-5-3-6.
Conclusion
It is essential to understand the Honda Odyssey firing order to know when there are problems with the cylinders.
A correct firing order gives you a smooth ride experience because it reduces vibrations caused by irregular power output.
This ensures that drivers and passengers get the most comfort while driving in a Hondas minivan.
When the cylinders are all firing correctly, you will also have minimal sound in the engine bay and the cabin area. This will also enhance the ride experience in the Honda Odyssey.
In addition, correct and refined firing order can help save on gas. This is demonstrated by the Hondas VCM system that deactivates some cylinders depending on the driving conditions.
It does this while still giving out decent power such that there is no reduction in driver experience.