Honda K20 engine

Describe what the car is doing — in plain English or as an OBD-II trouble code — and the AI works out which part is at fault, then walks you through replacing it in 3D.

1. Describe the fault. “Rough idle and P0301”, or “coolant smell after a long drive”. There is no menu to pick from — write it how you’d say it.
2. Read the diagnosis. You get the part, why it was chosen, what else is worth considering, and a parts & tools estimate.
3. Step through the repair. Back and Next walk the removal order, which is derived from how the parts actually fit together. Drag to orbit, scroll to zoom.

The engine modelled here is a Honda K20 — the Civic Si, RSX and Accord four-cylinder. Nothing is hardcoded to it, though: the AI reasons from your symptom rather than looking it up in a fault table, so the diagnosis holds up for most modern four-cylinder engines. Treat the 3D geometry and the specs as a demonstration, not a workshop manual.