AI Car Diagnostic Guide
Our AI analyzes your car's audio recording and identifies the likely fault from 19 documented conditions. Below is every condition we detect, with accuracy notes, severity, and repair cost estimates.
Overall accuracy: 76% top-1 · 88% top-3 · Near-100% on high-confidence classes
The diagnostic engine works by converting your recording into a dual-panel spectrogram — a visual representation of frequency versus time — and matching it against a library of confirmed fault signatures. Different mechanical failures produce distinct acoustic fingerprints: rod knock generates periodic low-frequency impacts at crankshaft frequency, wheel bearing failure produces a speed-proportional hum with characteristic amplitude modulation, and timing chain rattle appears as a transient broadband spike in the first seconds of cold startup.
Context you provide — when the sound occurs, whether it is speed-dependent or RPM-dependent, whether it is present at idle — is applied as a set of hard gates before visual analysis. A sound that only occurs under braking cannot be rod knock; a sound that disappears above 20 mph cannot be a failing starter. These constraints meaningfully improve precision on ambiguous recordings.
Twelve of the 19 conditions achieve near-100% top-1 accuracy. The remaining seven are limited by the physics of audio — several noise sources produce acoustically similar signatures and require supplemental OBD-II data or physical inspection for definitive identification. Those accuracy ceilings are documented on each condition's page.
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Rod Knock: Engine Bearing Failure
Near-100% top-1 detection accuracy
Rod knock occurs when a connecting rod bearing wears beyond its oil film tolerance. The rod, which connects the piston t...
Brake Wear Indicator: Metal-on-Metal Brake Contact
Near-100% top-1 detection accuracy
Modern brake pads include a hardened steel wear indicator tab that contacts the rotor when the friction material wears t...
Wheel Bearing Failure: Hub Noise and Growl
Near-100% top-1 detection accuracy
A wheel bearing is a sealed assembly of steel balls or rollers inside the wheel hub that allows the wheel to rotate with...
Power Steering Pump Noise
Near-100% top-1 detection accuracy
The hydraulic power steering pump pressurizes fluid to assist steering effort. When fluid is low, contaminated, or the p...
Bad Starter Motor: Cranking and Engagement Failure
Near-100% top-1 detection accuracy
The starter motor is an electric motor that cranks the engine to begin combustion. It engages the flywheel ring gear via...
Engine Misfire: Rough Running and Combustion Failure
Near-100% top-1 detection accuracy
An engine misfire occurs when a cylinder fails to complete a normal combustion event. This can be due to insufficient sp...
Timing Chain Rattle: Chain and Tensioner Failure
Near-100% top-1 detection accuracy
The timing chain synchronizes the rotation of the crankshaft and camshafts. As the chain stretches with age and the hydr...
Torque Converter Shudder
Near-100% top-1 detection accuracy
The torque converter clutch locks the converter mechanically to eliminate slippage at highway speeds, improving fuel eff...
Heat Shield Rattle
Near-100% top-1 detection accuracy
Heat shields are thin stamped metal panels bolted to the exhaust system and undercarriage to protect fuel lines, wiring,...
Differential Gear Whine
Near-100% top-1 detection accuracy
The differential contains a ring gear and pinion gear that transfer power from the driveshaft to the axle shafts. As the...
Valve Train and Lifter Noise
Near-100% top-1 detection accuracy
The valve train includes the camshaft, lifters (tappets), pushrods, rocker arms, and valves that open and close to allow...
Exhaust Leak
~80% top-1 detection accuracy
An exhaust leak occurs when combustion gases escape the exhaust system before reaching the muffler. This can happen at t...
Suspension Clunk
~67% top-1 detection accuracy
Suspension clunk is a broad category covering any metallic knocking or thudding sound that occurs when the suspension co...
Transmission Pump Whine
Physics-ceiling limited -- supplement with OBD-II codes
The automatic transmission hydraulic pump draws fluid from the pan and pressurizes it to actuate clutch packs and mainta...
Vacuum Leak
Physics-ceiling limited -- supplement with OBD-II codes
A vacuum leak occurs when air enters the intake manifold or associated vacuum-operated components at a point downstream ...
Accessory Belt Noise: Serpentine Belt and Pulley System
Physics-ceiling limited -- supplement with OBD-II codes
The serpentine or accessory drive belt transfers power from the crankshaft to the alternator, power steering pump, air c...
Turbocharger Whine
~33% top-1 detection accuracy
Turbochargers spin at up to 200,000 RPM to compress intake air. Some turbo noise is completely normal -- a subtle spool ...
Normal Vehicle Sounds
Physics-ceiling limited -- supplement with OBD-II codes
Modern vehicles produce a wide range of sounds during normal operation -- from the hum of tires on pavement to the tick ...
Metal-on-Metal Grinding
Near-100% top-1 detection accuracy
Metal-on-metal grinding occurs when two metal components that should never touch are brought into direct, high-force con...
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