The vehicle identification number (VIN) on a car contains a wealth of information about that specific automobile. By decoding the various characters and numbers in the VIN, you can find out details like the model year, manufacturer, plant location, and even the engine type. With a little decoding knowledge, the VIN can provide the answer to “what engine do I have?” without having to pop the hood and check for yourself.
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What is a VIN number?
The VIN is a unique 17-character serial number assigned to every vehicle produced and sold in the United States. It serves as the car’s fingerprint, distinguishing it from every other car on the road. First introduced in 1954, the VIN provides information about the vehicle’s characteristics and origins. Standardized by the National Highway Traffic Safety Administration, all vehicles manufactured after 1981 have a 17-character VIN that can be decoded to reveal specific details about that car.
Where is the VIN located?
The full VIN is printed in several locations on the vehicle. The most common places to find it are:
- On the driver’s side dashboard at the base of the windshield
- On the driver’s side door jamb
- On the engine block
- On the vehicle title
- On the registration card
- On the insurance documents
Be sure to only use the full 17-character VIN when decoding it, as partial VINs may not reveal the engine details you need.
How to decode a VIN
Decoding a VIN is a process that involves looking up the VIN’s alphanumeric characters in a database to unveil information about the vehicle. Here are the basic steps:
- Locate the full 17-character VIN.
- Break the VIN down into sections. It is divided into three parts:
- World Manufacturer Identifier (WMI) – first 3 digits
- Vehicle Descriptor Section (VDS) – next 6 digits
- Vehicle Identifier Section (VIS) – last 8 digits
- Identify the manufacturer and attributes based on each section:
- WMI – manufacturer, vehicle type, restraint system
- VDS – model, body type, engine type
- VIS – model year, manufacturing plant, and serial number
- Look up the VIN in a database to decode it. Many online sites and resources provide free VIN decoders.
- Review the decoded information, paying special attention to the engine specifications.
Decoding the engine type
When decoding a VIN to identify the engine, the key section to look at is the Vehicle Descriptor Section (VDS), positions 4-9. This section provides information about the vehicle’s engine type. Let’s take a closer look at how it works:
Positions 4-6
These digits identify the vehicle’s engine type. This is the most important part of the VIN for determining the engine. Common codes include:
| Digits | Engine |
|---|---|
| J72 | 5.7L Hemi V8 |
| W6A | 6.4L Turbo Diesel V8 |
| L20 | 2.0L Turbo 4-cyl |
| B12 | 1.2L Turbo 3-cyl |
As you can see, the three digits provide the key information about the engine’s size, cylinder layout, aspiration, and fuel type.
Positions 7-8
The next two digits provide additional details to pinpoint the exact engine version. For example, “J72” identifies a 5.7L Hemi V8. But the two digits that follow specify if it is a 5.7L Hemi VVT V8, a 5.7L Hemi Hybrid V8, a 5.7L Hemi FlexFuel V8, etc. This level of detail ensures the VIN identifies the precise engine model.
Position 9
The ninth digit is a “check digit” that validates the accuracy of the previous VIN sections. It is calculated based on a mathematical formula using the other digits.
By focusing on the 4-6 digits, you can narrow down the full engine name directly from the VIN. The remaining positions provide supplementary engine information to complete the identification.
Where to decode a VIN
Now that you understand what to look for in the VIN, where do you go to decode it? There are many free online VIN decoder tools and databases to help extract the engine details:
- CarMD – Provides a full vehicle history based on the VIN for free.
- VinFreeCheck – Free VIN lookup that decodes the basic specs including engine type.
- DMV.org – Allows you to decode any VIN number for free.
- NIC Insurance – Includes a VIN decoder that extracts the engine information.
- AutoZone – Its free VIN lookup tool provides engine details along with other specs.
Most automotive websites with VIN decoders can provide the vital engine information needed. Additionally, manufacturer websites like Ford, Toyota, and Volkswagen also have VIN decoding tools specific to their models.
Conclusion
The VIN number provides a wealth of coded data on your vehicle, including details on the type of engine under the hood. Focus on positions 4-6 of the VIN to narrow down the basic engine specs like size, cylinders, fuel type, and aspiration method. Then turn to a reputable VIN decoder tool online to look up the full details and get a definitive answer to “what engine do I have?” With a simple VIN lookup, you can take the guesswork out of identifying your car’s engine.