AUTOMOTIVE DIAGNOSTICS // TECHNICAL TOOLS
Diagnose smarter. Understand what the vehicle is telling you.
Practical automotive diagnostics, OBD-II information, calculators, electrical references, and technical tools built to help you troubleshoot logically.
01 // SYSTEM DIRECTORY
What are you working on?
Start with a symptom, trouble code, calculation, or technical reference.
Diagnostics
Troubleshoot problems by symptom and work through logical diagnostic procedures.
OPEN DIAGNOSTICS →OBD-II Codes
Look up diagnostic trouble codes, symptoms, likely causes, and testing information.
SEARCH CODES →Calculators & Tools
Tire sizing, voltage drop, gear ratios, electrical calculations, fuel costs, and more.
OPEN TOOLS →Technical Reference
Charts, conversions, specifications, electrical information, and workshop references.
OPEN REFERENCE →02 // COMMON DIAGNOSTICS
Start with the symptom
Car Cranks But Won't Start
Work through spark, fuel, compression, security, and electrical checks.
ELECTRICALBattery Keeps Dying Overnight
Test for excessive key-off current draw and isolate the circuit causing it.
STARTING SYSTEMCar Clicks But Won't Start
Determine whether the problem is the battery, cables, starter, or control circuit.
03 // TECHNICAL TOOLS
Calculate before you guess
Voltage Drop Calculator
Calculate circuit voltage drop and percentage loss.
TIRE-01Tire Size Calculator
Compare tire diameter, circumference, revolutions per mile, and speedometer difference.
DRIVE-01RPM & Gear Ratio Calculator
Calculate engine RPM from speed, tire diameter, axle ratio, and transmission gearing.
ELEC-02Ohm's Law Calculator
Calculate voltage, current, resistance, and electrical power from known values.
FUEL-01Fuel Cost Calculator
Estimate trip or monthly fuel cost using distance, fuel economy, and fuel price.
FUEL-02MPG Calculator
Calculate fuel economy using distance traveled and fuel consumed.
TORQDEX // SYSTEM PURPOSE
Better diagnostics start with better information.
TorqDex is a practical automotive knowledge base focused on logical troubleshooting, useful calculations, and technical reference material without burying the answer under filler.