CURATED AUTOMOTIVE DIRECTORY
By Symptom
Start with what the driver can see, hear, feel, or smell, then narrow the cause with evidence.
ARTICLES & MATERIALS
Start with these guides
Some guides also appear in related directories. Each article has one canonical page and one maintained body of content.
Rough Idle After Warm-Up: A Diagnostic Path
A warm-engine rough idle is a condition to measure, not a reason to order an idle valve, injector, or ignition coil.
Read guideCranks but Will Not Start: The First Five Checks
A no-start diagnosis moves quickly when cranking speed, module communication, spark or ignition command, injector command, and mechanical timing are checked in order.
Read guide
Intermittent Stall: What to Log Before Restarting
The few seconds around an intermittent stall contain more evidence than a normal-running inspection after the engine restarts.
Read guide
Engine Overheats in Traffic but Not on the Highway
An overheat that appears at low road speed often points toward airflow or fan-control evidence, but coolant level, circulation, pressure, and sensor accuracy still need confirmation.
Read guide
Brake Pedal Pulsation: Speed-Based Checks Before Parts
Pedal pulsation can reflect disc thickness variation, hub runout, wheel-speed control activity, or looseness; the road-speed pattern helps separate them.
Read guideBattery Drains Overnight: A Parasitic-Draw Test Plan
An overnight discharge requires separate proof of battery capacity, charging performance, and key-off current after the vehicle has entered sleep mode.
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A/C Blows Warm at Idle: Diagnostic Checks That Matter
Warm air at idle may follow low condenser airflow, compressor-control limits, refrigerant charge issues, engine cooling strategy, or a blend-door problem.
Read guideReduced-Power Warning: Data to Save Before Cycling the Key
A reduced-power strategy protects the vehicle after the controller detects an implausible input, actuator response, temperature, pressure, or network state.
Read guideUse these guides to plan checks, not to replace model-specific service information. Stop when a procedure involves unsupported lifting, pressurized fuel, pyrotechnic restraints, refrigerant recovery, or high-voltage isolation beyond your training and equipment.