Intermittent rough idle and shaking on 2019 Lexus NX300 with recurring diagnostic trouble codes, despite multiple repairs, and no mechanic can replicate the issue at the shop.

Workarounds Described

• Swapped ignition coils to see if misfire codes follow, but they didn't
• Took car to second mechanic while CEL was on, but symptom disappeared upon arrival
• Asked shop to do cylinder leak-down test and attached photo of results

Implied Software Gaps

• Continuous OBD2 data logger that can capture intermittent faults and provide diagnostic interpretation when no check engine light is present

IntermittentCatch Pro

A mobile diagnostics app that continuously logs live OBD2 data (fuel trims, misfire counts, sensor voltages) and uses machine learning to detect intermittent patterns, even when the check engine light is off. It provides actionable diagnostic suggestions based on the logged data, eliminating the need to catch the fault at the shop.

Existing Solutions Mentioned