No. 03
On the AI.
An honest account of what the model can and cannot do, and what you should assume when reading a report.
Body
§ 01What the model is
Revly uses machine-learning models to analyze engine audio recordings and predict mechanical conditions. The models are trained on a curated dataset of engine recordings paired with verified mechanical outcomes — bench tests, teardowns, and confirmed shop diagnoses. They are not symbolic systems and they do not "understand" engines in any meaningful sense; they identify acoustic patterns that have, in the training data, been associated with specific conditions.
§ 02What it produces
The model produces probabilistic findings, not direct measurements. A diagnosis is a prediction. Even high-confidence findings can be wrong, and even low-confidence findings can be right. Confidence scores are calibrated to be meaningful, but they are not certainties.
§ 03It is not a mechanic
Revly is an early-warning tool. It is not a certified inspection. It should not be the sole basis for major repair decisions or for deciding whether a vehicle is safe to operate. Verify findings with a qualified mechanic before authorizing significant work.
§ 04Acoustic limitations
Sound-based diagnostics have inherent limits. Accuracy is affected by ambient noise, microphone quality and positioning, engine load conditions, exhaust configuration, vehicle age, aftermarket modifications, and the presence of multiple overlapping issues. Low-quality recordings produce lower-confidence diagnoses; the app rates recording quality before submission.
§ 05Cost estimates are approximate
Repair cost ranges in our reports are based on aggregated typical pricing for your vehicle's make, model, and approximate region. Actual costs vary substantially based on shop, location, parts availability, and the specific scope of repair determined by physical inspection.
§ 06Coverage varies
Detection accuracy is highest for well-represented engine families in our training data. Common vehicles produce more reliable results; rare, vintage, or heavily modified engines produce less reliable results. Diesel coverage is currently more limited than gasoline.
§ 07The model improves over time
We continuously expand the training set and refine the model as verified mechanical outcomes accumulate. The failure-mode library and overall accuracy grow over time. If you notice a diagnosis that does not match your mechanic's findings, please report it — in either direction. Both confirmations and corrections improve subsequent editions.
§ 08Your judgment matters
You are solely responsible for decisions about your vehicle's operation, maintenance, and repair. Revly is a tool to enhance your awareness and inform your conversations with mechanics; it does not replace training, professional inspection, or your own judgment. When in doubt about whether a vehicle is safe to drive, do not drive it. Call a tow.
Questions about how our AI works or about a specific finding? Write to ekowalski@justrevly.com.