Fuel Type by VIN: What a VIN Decode Actually Returns
Does a VIN show fuel type? NHTSA's vPIC returns FuelTypePrimary and FuelTypeSecondary for most vehicles. See all 14 values and what a VIN never carries.
NHTSA vPIC has the field, but manufacturers leave it blank on many vehicles. A blank is not an error, and no other decoder can fill it.
A VIN decode returns fuel type for most vehicles: NHTSA's free vPIC database exposes FuelTypePrimary and FuelTypeSecondary, drawn from the manufacturer's own 49 CFR Part 565 submittal. It is not universal — the field comes back blank on some records, mostly pre-2005 vehicles and VIN patterns the manufacturer never fully submitted. vPIC carries no octane rating, tank size, or MPG.
How do I find the fuel type from a VIN?
- Enter the full 17-character VIN at free-vin-lookup.com/check, which decodes through NHTSA's vPIC database. Add the model year if the VIN is pre-1981 or if the decode returns an error code.
- Read FuelTypePrimary. This is the fuel the manufacturer filed for that VIN pattern, and it is always one of 14 fixed values including Gasoline, Diesel, Electric, Fuel Cell and Ethanol (E85).
- Read FuelTypeSecondary. It is blank by design on single-fuel vehicles and fills in only for hybrids, plug-in hybrids and flex-fuel vehicles.
- Read ElectrificationLevel to separate BEV, PHEV, strong HEV, mild HEV and FCEV. Note the ordering rule: Electric primary with Gasoline secondary means the vehicle plugs in; Gasoline primary with Electric secondary means it does not.
- Cross-check the result against EngineModel, DisplacementL and EngineCylinders in the same response. Fuel is derived from the engine character in the VIN, so a diesel result should be paired with a diesel engine code.
- If FuelTypePrimary comes back blank, stop relying on the decode for fuel and read the fuel filler door label and the underhood emissions (VECI) label instead.
All 14 valid FuelTypePrimary values in NHTSA vPIC, from the API's own GetVehicleVariableValuesList endpoint, with what each means and what vPIC typically returns alongside it. The same 14 values are valid for FuelTypeSecondary.
| vPIC value ID | FuelTypePrimary value | What it means | What vPIC typically returns alongside |
|---|---|---|---|
| 1 | Diesel | Compression-ignition diesel engine | Secondary blank; ElectrificationLevel blank. Seen on 2014 Silverado 2500, 2018 Ram 2500, 2016 Colorado Duramax, 2017 F-250 |
| 2 | Electric | Electric drive is the primary power source | Secondary blank plus ElectrificationLevel 'BEV' on a pure EV; Secondary 'Gasoline' plus 'PHEV' on a plug-in hybrid |
| 4 | Gasoline | Spark-ignition gasoline engine | Secondary blank on a conventional car; Secondary 'Electric' plus an HEV ElectrificationLevel on a non-plug-in hybrid; Secondary 'Ethanol (E85)' or 'Flexible Fuel Vehicle (FFV)' on a flex-fuel vehicle |
| 6 | Compressed Natural Gas (CNG) | Dedicated CNG engine, common on fleet and vocational trucks | Secondary 'Gasoline' on a bi-fuel conversion; otherwise blank |
| 7 | Liquefied Natural Gas (LNG) | Cryogenic liquefied natural gas, mainly Class 7-8 tractors | Secondary usually blank |
| 8 | Compressed Hydrogen/Hydrogen | Hydrogen stored as compressed gas, including combustion applications | Secondary usually blank; distinct from the Fuel Cell value |
| 9 | Liquefied Petroleum Gas (propane or LPG) | Propane autogas, common on shuttle buses and forklifts | Secondary 'Gasoline' on a bi-fuel setup |
| 10 | Ethanol (E85) | Up to 85% ethanol blended with gasoline | Most often appears as the secondary value with 'Gasoline' primary, as on a 2013 Impala and 2015 Silverado |
| 11 | Neat Ethanol (E100) | Pure ethanol; effectively absent from the U.S. light-vehicle fleet | Rare in practice |
| 13 | Methanol (M85) | Up to 85% methanol blended with gasoline; 1990s pilot fleets only | Rare in practice |
| 14 | Neat Methanol (M100) | Pure methanol; effectively absent from the U.S. fleet | Rare in practice |
| 15 | Flexible Fuel Vehicle (FFV) | Vehicle certified to run gasoline or E85 interchangeably | Appears as the secondary value with 'Gasoline' primary on some records, such as a 2017 Expedition, where other makes use 'Ethanol (E85)' instead |
| 17 | Natural Gas | Natural gas where the manufacturer did not specify CNG or LNG | Secondary usually blank |
| 18 | Fuel Cell | Hydrogen fuel cell electric drive | Seen on a 2019 Toyota Mirai, which returned ElectrificationLevel blank rather than 'FCEV' |
Where the VIN route stops for fuel type
- FuelTypePrimary comes back empty on a real share of records. Test VINs for a 1994 Chevrolet Cavalier, 1999 VW Beetle, 2000 GMC Sierra, 2005 Audi and 2020 Hyundai Tucson each returned a model year but no fuel type. NHTSA states vPIC is populated from manufacturers' 49 CFR Part 565 submittals, so an attribute the manufacturer never filed returns blank with no fallback value.
- There is no octane or fuel-grade field. Neither DecodeVinValues nor DecodeVinValuesExtended, both of which return 154 fields, carries required octane, premium-versus-regular, or diesel and DEF grade. FuelTypePrimary stops at the word 'Gasoline'.
- Flex-fuel labeling is inconsistent. A 2015 Chevrolet Silverado returned FuelTypeSecondary 'Ethanol (E85)', a 2017 Ford Expedition returned 'Flexible Fuel Vehicle (FFV)', and other flex-fuel-capable vehicles returned only 'Gasoline' with a blank secondary. A blank secondary does not prove a vehicle is not FFV.
- No fuel tank capacity and no fuel economy. FuelTankType and FuelTankMaterial exist, but NHTSA's own variable descriptions define both for motorcycles, and both were empty on every car and truck tested. MPG is EPA data published at fueleconomy.gov, not NHTSA data.
- A VIN that fails validation loses the entire engine block. A 2017 Toyota RAV4 test VIN with a bad check digit returned error codes 1, 4 and 14 with fuel type, cylinders and displacement all blank. Separately, a 2019 Toyota Mirai returned FuelTypePrimary 'Fuel Cell' but left ElectrificationLevel empty instead of 'FCEV'.
Where to get it instead
- Fuel filler door and fuel cap label. EPA-required labeling names the fuel and the minimum octane the engine was certified on. On GM, Ford and Chrysler flex-fuel vehicles, a yellow fuel cap or yellow filler-neck ring, or an E85 or FlexFuel badge, marks E85 capability. This is the most reliable check when vPIC's FuelTypeSecondary is blank.
- Underhood Vehicle Emission Control Information (VECI) label. Required by 40 CFR Part 86, this label states the engine family, displacement and the fuel the engine was certified on. It is the best fallback for pre-2005 vehicles, which is exactly where FuelTypePrimary is most likely to come back empty. Source →
- fueleconomy.gov (U.S. DOE and EPA). Search by year, make, model and trim for fuel type, recommended or required octane, fuel tank capacity and city/highway MPG. This covers every fuel-related number vPIC does not carry, though it is keyed to model and trim rather than to your individual VIN. Source →
- Owner's manual or a franchised dealer parts department. The manual states the required fuel and octane for that exact build. A franchised dealer can pull the original build record by VIN, which resolves engine-option and flex-fuel questions that vPIC leaves ambiguous or blank.
Primary sources
Open the underlying public source and verify that its scope matches the question you are asking.
- vPIC Decode VIN (Values) API and dataset notesNHTSA, U.S. Department of Transportation
- Valid values for Fuel Type - Primary (14 values)NHTSA vPIC
- Valid values for Electrification Level (6 values)NHTSA vPIC
- 49 CFR 565.15 Content requirements, Table I (VIN positions 4-8 must identify engine type)U.S. National Archives, eCFR
- Find and Compare Cars - fuel type, octane and tank capacityU.S. Department of Energy and EPA
Fuel Type by VIN: What a VIN Decode Actually Returns — questions
What is the best way to identify whether my truck is gas or diesel using the VIN?
Decode the VIN and read FuelTypePrimary. Fuel tracks the engine character in the VIN's descriptor section, so it separates engine options within one model line. A 2016 Chevrolet Colorado with the 2.8L Duramax returns FuelTypePrimary "Diesel"; the same year with the 3.6L V6 returns "Gasoline." A 2017 Ford F-250 test VIN also returned "Diesel."
How can I decode my Duramax VIN to find out the engine and fuel details?
Run the VIN through NHTSA's vPIC decoder, free at free-vin-lookup.com/check. A 2016 Colorado Duramax VIN returns FuelTypePrimary "Diesel," EngineModel "LWN - EUR04, DI: Direct Injection," DisplacementL 2.8, EngineCylinders 4, EngineKW 140, and Turbo "Yes." That is the manufacturer's own engine submittal, not a guess from the model name.
Can I check the VIN of my car at AutoZone and find details like fuel type or year?
Parts counters look up year, make, model and engine to sell you the right part; they are not the source for fuel type. The free public source is NHTSA's vPIC decoder, which returns ModelYear and FuelTypePrimary directly from the manufacturer's 49 CFR Part 565 filing. Use it before you rely on a counter lookup.
Does a VIN tell me if my car is a hybrid or a plug-in hybrid?
Yes, and the field order is the tell. Plug-in hybrids return FuelTypePrimary "Electric" with FuelTypeSecondary "Gasoline" - verified on a 2018 Prius Prime, 2022 RAV4 Prime and 2023 Pacifica. Hybrids that never plug in reverse it: "Gasoline" primary, "Electric" secondary, as on a 2018 Prius. ElectrificationLevel names the type outright.
How do I tell if my vehicle is flex fuel and can run E85?
Check FuelTypeSecondary, but do not trust a blank. vPIC labels flex fuel inconsistently: a 2015 Silverado returned "Ethanol (E85)" while a 2017 Expedition returned "Flexible Fuel Vehicle (FFV)," and some flex-fuel vehicles return only "Gasoline." Confirm at the fuel filler door - a yellow cap or ring, or an E85 badge, marks a flex-fuel vehicle.
Does the VIN decode tell me what octane gas my car needs?
No. vPIC has no octane, fuel grade, or premium-versus-regular field anywhere in its 154 returned variables. FuelTypePrimary says "Gasoline," not which grade. The required octane is printed on the fuel filler door label and in the owner's manual, and DOE/EPA lists it per trim at fueleconomy.gov.
How can I identify the year and engine or fuel type of an older car like an Acura Vigor?
Decode it, but expect gaps. vPIC returns ModelYear for nearly every 1981-and-later VIN, and fuel type for most. Coverage thins on older records: test VINs for a 1994 Cavalier, 1999 Beetle and 2000 Sierra returned ModelYear but a blank FuelTypePrimary. For those, read the underhood emissions label.
Why did the fuel type come back blank for my VIN?
Because vPIC only has what the manufacturer filed. NHTSA states the dataset is populated from manufacturers' 565 submittals, so an attribute never submitted for that VIN pattern returns empty, with no substitute. Decode errors also blank it: a test VIN with a bad check digit returned error codes 1, 4 and 14 and no fuel type.