Spool Mercedes M278 Wireless Ethanol Analyzer Kit & 10 Micron Filter Unit

Spool Mercedes M278 Wireless Ethanol Analyzer Kit & 10 Micron Filter Unit

The Spool wireless ethanol analyzer displays the actual ethanol content and fuel temperature on a smartphone. It is especially useful on cars running E85 or custom ethanol blends where the calibration expects a known ethanol percentage.

Fuel sold as E85 does not always contain exactly 85% ethanol. Spool notes that E85-rated fuel may contain roughly 51–85% ethanol, so measuring the fuel in the tank removes the guesswork when preparing a blend.

How it works

• A GM/Continental-type ethanol sensor measures ethanol content and fuel temperature
• Bluetooth Low Energy sends live data to the phone with very low power consumption
• The free Spool app shows the reading and includes an ethanol mix calculator
• Vehicle-specific fittings and adapters allow a clean installation with the factory fuel lines

This is a useful addition to a tuned car where fuel composition directly affects the calibration and safe engine operation.