Section 2.0 · The station list

Sounds it knows.

Twenty nine sounds across nine systems, learned from real recordings of real failures. Each one below is a station on the tuner. Find yours, then let the app confirm it by ear.

2.1

Engine

Engine · bottom end

Engine knock

A deep steady hammering that speeds up with the engine. Worn bearings until proven otherwise. Stop driving and check the oil.

Engine · bottom end

Rod knock

The serious version of engine knock. Deep and rhythmic, louder under load. This one ends engines.

Engine · combustion

Spark knock

Metallic pinging under load, like marbles in a can. Wrong fuel, carbon buildup, or timing.

Engine · valvetrain

Engine tick

A light rapid tick from the top of the engine. Often low oil or lifters. Sometimes normal on direct injection.

Engine · timing

Timing chain rattle

A rattle from the front cover, worst on cold start. A stretched chain or a tired tensioner.

Engine · timing

Timing drift

Timing that has wandered. Rough running with rattle. Needs a shop before it needs a new engine.

Engine · Honda VTEC

VTEC failure

A Honda that rattles where it should sing. Usually a solenoid or an oil pressure problem.

Engine · Honda VTEC

VTEC engagement

The Honda crossover growl. Normal when healthy. The tuner knows the difference.

Engine · Honda VTEC

VTEC solenoid tick

A tick near the solenoid, often with a warning light. A dirty screen is common. Cheap if caught early.

2.2

Turbo and boost

Turbo

Turbo failure

A whine or screech that rises with boost. Bearings or the wheel itself.

Turbo

Boost leak

A whoosh under throttle and power that went missing. A split hose or a loose clamp.

Turbo

Wastegate rattle

A metallic buzz at idle from the turbo. The actuator linkage has play.

2.3

Belts and accessories

Accessory drive

Belt squeal

The classic squeal on startup or in the rain. The belt or its tensioner.

Accessory drive

Pulley noise

A chirp or knock that follows engine speed. A pulley bearing on its way out.

Accessory drive

Alternator whine

An electrical whine that climbs with revs. Bearings or diodes inside the alternator.

Accessory drive

AC compressor noise

A grind or rapid click when the AC kicks on. The clutch or the compressor itself.

Accessory drive

Power steering groan

A groan when you turn, worst at parking speed. Low fluid or a tired pump.

2.4

Brakes

Brakes

Brake squeal

A high squeal when braking. Wear indicators doing their one job. Pads are due.

Brakes

Brake grinding

Metal on metal. The pad is gone and the rotor is paying for it. Stop soon.

2.5

Wheels and axles

Wheel end

Wheel bearing hum

A hum that rises with road speed and changes when you swerve. Usually a bearing, not a tire.

Axle

CV joint click

Clicking in tight turns under power. The outer joint is dry or worn.

2.6

Exhaust

Exhaust

Exhaust leak tick

A tick that fades as the engine warms. A cracked manifold or a failed gasket. Can leak fumes.

Exhaust

Heat shield rattle

A tinny buzz at certain revs from under the car. A loose shield. Annoying and cheap.

Exhaust

Catalytic converter rattle

A marble shake from under the floor. The insides of the cat have broken up.

2.7

Transmission and driveline

Transmission

Transmission fault

Whining, clunking, or slipping between gears. Check the fluid before anything else.

Driveline

Differential whine

A gear whine that follows road speed, louder on and off the throttle. Ring and pinion wear.

2.8

Cooling

Cooling

Water pump growl

A growl or whine from the pump, sometimes with coolant weeping below. The bearing is going.

Cooling

Head gasket bubbling

Bubbling in the coolant tank and a sweet smell. Combustion is getting where it should not.

2.9

Intake

Intake

Vacuum leak hiss

A sharp hiss at idle with a rough, hunting engine. A cracked hose letting air sneak in.

YOUR CAR MAKES A SOUND THAT IS NOT ON THIS PAGE?

The app also knows what healthy sounds like, and it says when it is not sure. Record it and find out.

Fig 4. The library grows. Every contributed recording teaches the next version.