* If your Regal is a flex-fuel vehicle (FFV): It's designed to run on E85 (85% ethanol, 15% gasoline) and gasoline. You'll likely see slightly reduced fuel economy compared to gasoline, but it should run without problems. Check your owner's manual for specific recommendations regarding E85 use.
* If your Regal is *not* a flex-fuel vehicle: Using E85 will likely cause significant problems. E85 is corrosive and can damage components not designed to handle its higher ethanol content. This can lead to:
* Engine damage: Ethanol can damage rubber seals, fuel lines, and other engine components.
* Reduced fuel economy: Significantly lower mileage than gasoline.
* Poor performance: Rough running, stalling, and lack of power.
* Voiding your warranty: Using the wrong fuel is almost certainly a violation of your warranty.
How to tell if your Buick Regal is an FFV:
1. Check the fuel filler door: FFVs usually have a sticker clearly stating "E85" or "Flex Fuel" near the fuel filler.
2. Consult your owner's manual: The manual will explicitly state whether your vehicle is compatible with E85.
3. Check your vehicle identification number (VIN): Your VIN might contain a code indicating flex-fuel capability, but this is less reliable than the other methods.
In short: Only use E85 in a Buick Regal specifically designed as a flex-fuel vehicle. Using it in a non-FFV car will likely result in costly repairs.
