This module uses normalized blend, contamination, material-compatibility and calibration values to teach diagnostic relationships. It does not define legal fuel specifications, approved blend limits, drain/disposal procedures, sampling methods, fuel-system repair authorization or OEM material compatibility. Use current vehicle/fuel labeling, manufacturer service information, approved containers/PPE and local environmental/safety procedures.
Compatibility means chemistry + materials + calibration + condition
Biofuel diagnosis gets easier when students stop treating ethanol, biodiesel and renewable diesel as one category. This module asks four questions in order: What fuel is actually present? Is that composition approved? Can the materials and control strategy tolerate it? Is the fuel still in good condition?
Separate blend chemistry from vehicle compatibility
Model how composition, contamination, materials and calibration interact
The inputs are fictional 0–100 teaching indexes. They intentionally do not represent real blend limits, water thresholds, material ratings or calibration tolerances.
*Normalized teaching indexes only. A real fuel decision requires the exact fuel standard, vehicle approval, sample/test method, ambient condition and service information.
Identify → verify approval → inspect quality/materials → compare control evidence
Ordered biofuel-compatibility workflow
Complete the sequence in order.
Evidence
Best supported conclusion / next step
10-question knowledge check
Compatibility reasoning is evidence work, not permission to improvise with fuel
Use safe training aids, sealed samples when appropriate and exact service information. Instructor observation should emphasize identification, evidence, compatibility research and verification—not unapproved blending, draining, venting or pressurized-system service.
Student: ____________________ Date: __________ Instructor: ____________________