Chevy 4.3 V6 firing order and cylinder numbers (Vortec 4300)
The Chevrolet 4.3 V6 (Vortec 4300) fires 1-6-5-4-3-2. Cylinder 1 is the front cylinder on the driver side (bank 1, left bank).
Drag to turn the engine, scroll or pinch to zoom. Orange = the cylinder firing now; the numbers on the coils are cylinder numbers. Driver and passenger sides are for left-hand-drive vehicles.
Firing order diagram
Where each cylinder is
| Cylinder | Misfire code | Location | Place in firing order |
|---|---|---|---|
| 1 | P0301 | The front cylinder on the driver side (bank 1, left bank) | 1st |
| 2 | P0302 | The front cylinder on the passenger side (bank 2, right bank) | 6th |
| 3 | P0303 | The second cylinder from the front on the driver side (bank 1, left bank) | 5th |
| 4 | P0304 | The second cylinder from the front on the passenger side (bank 2, right bank) | 4th |
| 5 | P0305 | The rear cylinder on the driver side (bank 1, left bank) | 3rd |
| 6 | P0306 | The rear cylinder on the passenger side (bank 2, right bank) | 2nd |
Bank 1 is always the bank that contains cylinder 1, so for this engine bank 1 is the left bank with cylinders 1-3-5; bank 2 is the right bank with cylinders 2-4-6. Oxygen-sensor, camshaft and catalyst codes that name bank 1 or bank 2 use the same split.
Coils, plugs and wires
- Distributor ignition on the engines covered here: the plug wires leave the cap in the order 1-6-5-4-3-2, starting from the terminal the rotor points to with cylinder 1 at top dead centre on compression.
How to find a cylinder on this engine
- Find the front of the engine: the end with the drive belt and pulleys.
- Find bank 1, the left bank that holds cylinder 1. On this engine it is the driver side.
- Count from the belt end. Cylinders 1-3-5 run along bank 1 and 2-4-6 along bank 2, each starting at the belt end.
- Match the code: P0301 is cylinder 1, P0302 cylinder 2, and so on. P0300 means a random or multiple misfire and does not name a cylinder.
Which engines this covers
The GM 90-degree 4.3 V6 (262 cu in, Vortec 4300) in trucks, vans and SUVs, verified against GM service manuals for the 1995 C1500 and the 2005 Blazer. The 2014-on 4.3 LV3 is not covered on this page.
- Chevrolet C/K 1500 and Silverado 4.3 (1995 verified)
- S-10 and Blazer 4.3 (2005 Blazer verified)
- Astro and G-series vans 4.3
Questions
What is the Chevy 4.3 V6 (Vortec 4300) firing order?
1-6-5-4-3-2.
Which side is cylinder 1 on?
Cylinder 1 is the front cylinder on the driver side (bank 1, left bank).
Where is cylinder 4 (code P0304)?
Cylinder 4 is the second cylinder from the front on the passenger side (bank 2, right bank).
Which bank is bank 1?
The bank with cylinder 1: the left bank, cylinders 1-3-5.
Is the 4.3 V6 numbered like a Chevy V8?
Yes. Odd cylinders 1-3-5 are on the driver side and even cylinders 2-4-6 on the passenger side, numbered from the front, just as on the small-block V8.
Sources
The firing order, the cylinder numbering and the position of each bank in the vehicle were each checked against at least two of these sources, and they agree.
- GM service manual, 1995 Chevrolet C1500 4.3L, Ignition Firing Order (via Operation CHARM). “Firing Order 1-6-5-4-3-2” Factory / manufacturer
- GM service manual, 2005 Chevrolet Blazer 4.3L, Firing Order and Number One Cylinder: Locations (via Operation CHARM). “Firing Order 1-6-5-4-3-2. Diagram: front of vehicle at the bottom; 1-3-5 driver side, 2-4-6 passenger side.” Factory / manufacturer
- Engine-build.com, GM 4.3 V6 (Vortec 4300) firing order. “Firing order: 1-6-5-4-3-2. Cylinder numbering: Left bank 1-3-5, right bank 2-4-6.” Independent reference
- VehicleFixation, Chevy 4.3 firing order and cylinder diagram. “Firing order 1-6-5-4-3-2; cylinders 1, 3, 5 on the driver side.” Independent reference
Last reviewed 15 November 2026 · How the data is sourced and checked