Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Quick Diagnostic Chart
X: Applied
| Troubleshooting item | Starter motor malfunction (Mechanical or electrical) | Starter circuit including ignition switch is open | Starter relay or related circuit malfunction | Improper engine oil level | Low or dead battery | Charging system malfunction | Improper engine compression | Improper valve timing | Hydrolocked engine | Improper engine oil viscosity | Improper dipstick | Base engine malfunction | Flywheel (MTX)/Drive plate (ATX) is seized | Improper tension or damaged drive belts | Improper engine coolant level | Water and anti-freeze mixture is improper | Cooling system malfunction (Radiator, hoses, overflow system, thermostat etc.) | Cooling fan system malfunction | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Blown fuses | |||||||||||||||||||
| 2 | Check engine light illuminates | |||||||||||||||||||
| 3 | Will not crank | X | X | X | X | X | X | X | ||||||||||||
| 4 | Hard to start/long crank/erratic start/erratic crank | X | X | |||||||||||||||||
| 5 | Engine stalls | After start/at idle | X | X | ||||||||||||||||
| 6 | Cranks normally but will not start | X | X | |||||||||||||||||
| 7 | Slow return to idle | X | ||||||||||||||||||
| 8 | Engine runs rough/rolling idle | X | X | |||||||||||||||||
| 9 | Fast idle/runs on | |||||||||||||||||||
| 10 | Low idle/stalls during deceleration | |||||||||||||||||||
| 11 | Engine stalls/quits | Acceleration/cruise | X | X | ||||||||||||||||
| Engine runs rough | Acceleration/cruise | X | X | |||||||||||||||||
| Misses | Acceleration/cruise | X | X | |||||||||||||||||
| Buck/jerk | Acceleration/cruise/deceleration | X | X | |||||||||||||||||
| Hesitation/stumble | Acceleration | X | X | |||||||||||||||||
| Surges | Acceleration/cruise | X | X | |||||||||||||||||
| 12 | Lack/loss of power | Acceleration/cruise | X | X | ||||||||||||||||
| 13 | Knocking/pinging | Acceleration/cruise | X | X | ||||||||||||||||
| 14 | Poor fuel economy | X | X | X | ||||||||||||||||
| 15 | Emission compliance | X | X | X | X | |||||||||||||||
| 16 | High oil consumption/leakage | X | X | X | ||||||||||||||||
| 17 | Cooling system concerns | Overheating | X | X | X | X | X | |||||||||||||
| 18 | Cooling system concerns | Runs cold | X | X | ||||||||||||||||
| 19 | Exhaust smoke | X | X | X | ||||||||||||||||
| 20 | Fuel odor (in engine compartment) | |||||||||||||||||||
| 21 | Engine noise | X | X | X | ||||||||||||||||
| 22 | Vibration concerns (engine) | X | ||||||||||||||||||
| 23 | A/C does not work sufficiently | |||||||||||||||||||
| 24 | A/C is always on or A/C compressor runs continuously | |||||||||||||||||||
| 25 | A/C is not cut off under wide open throttle conditions | |||||||||||||||||||
| 26 | Exhaust sulphur smell | |||||||||||||||||||
| 27 | Fuel refill concerns | |||||||||||||||||||
| 28 | Fuel filling shut off concerns | |||||||||||||||||||
| 29 | Spark plug condition | X | ||||||||||||||||||
| 30 | ATX concerns | Upshift/downshift/engagement | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [FS5A-EL] .) | |||||||||||||||||
X: Applied
| Troubleshooting item | Engine and transaxle mounts are improperly installed | Cooling fan sheet is improperly installed | Cruise control system operation improperly (Vehicles with cruise control system) | Fuel quality | Variable valve timing system malfunction | Variable tumble system malfunction | Engine overheating | Air cleaner element clogged | Air leakage from intake-air system (Loose tubes, cracks breakage) | Intake air temperature is too hot | Idle learning of drive-by-wire control system is not completed | Drive-by-wire control system improper operation | Throttle body malfunction (stuck open or close, restriction) | Drive-by-wire control system operates with brake override system | Variable intake-air system malfunction | Vacuum leakage (vacuum hose damage, misrouting) | Ignition coil malfunction (e.g. open, short or cracks) | Initial ignition timing misadjustment (CKP sensor and crankshaft pulley misadjustment) | Spark plug malfunction | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Blown fuses | ||||||||||||||||||||
| 2 | Check engine light illuminates | X | X | X | |||||||||||||||||
| 3 | Will not crank | ||||||||||||||||||||
| 4 | Hard to start/long crank/erratic start/erratic crank | X | X | X | X | X | X | X | X | X | |||||||||||
| 5 | Engine stalls | After start/at idle | X | X | X | X | X | X | X | X | X | ||||||||||
| 6 | Cranks normally but will not start | X | X | X | X | X | X | X | X | ||||||||||||
| 7 | Slow return to idle | X | X | ||||||||||||||||||
| 8 | Engine runs rough/rolling idle | X | X | X | X | X | X | X | X | X | X | ||||||||||
| 9 | Fast idle/runs on | X | X | X | |||||||||||||||||
| 10 | Low idle/stalls during deceleration | X | X | X | |||||||||||||||||
| 11 | Engine stalls/quits | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | ||||||||
| Engine runs rough | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | ||||||||||
| Misses | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | |||||||||
| Buck/jerk | Acceleration/cruise/deceleration | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||
| Hesitation/stumble | Acceleration | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||
| Surges | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | |||||||||
| 12 | Lack/loss of power | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | ||||||
| 13 | Knocking/pinging | Acceleration/cruise | X | X | |||||||||||||||||
| 14 | Poor fuel economy | X | X | X | X | X | X | ||||||||||||||
| 15 | Emission compliance | X | X | X | X | X | |||||||||||||||
| 16 | High oil consumption/leakage | ||||||||||||||||||||
| 17 | Cooling system concerns | Overheating | |||||||||||||||||||
| 18 | Cooling system concerns | Runs cold | |||||||||||||||||||
| 19 | Exhaust smoke | X | X | X | |||||||||||||||||
| 20 | Fuel odor (in engine compartment) | ||||||||||||||||||||
| 21 | Engine noise | X | X | ||||||||||||||||||
| 22 | Vibration concerns (engine) | X | X | ||||||||||||||||||
| 23 | A/C does not work sufficiently | ||||||||||||||||||||
| 24 | A/C is always on or A/C compressor runs continuously | ||||||||||||||||||||
| 25 | A/C is not cut off under wide open throttle conditions | ||||||||||||||||||||
| 26 | Exhaust sulphur smell | X | X | X | |||||||||||||||||
| 27 | Fuel refill concerns | ||||||||||||||||||||
| 28 | Fuel filling shut off concerns | ||||||||||||||||||||
| 29 | Spark plug condition | X | X | ||||||||||||||||||
| 30 | ATX concerns | Upshift/downshift/engagement | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [FS5A-EL] .) | ||||||||||||||||||
X: Applied
| Troubleshooting item | Erratic signal to ignition coil | CKP sensor is damaged (e.g. open or short circuit) | Crankshaft pulley is damaged | Improper gap between CKP sensor and crankshaft | Fuel pump malfunction (Mechanically or electrically) | Pressure regulator malfunction | Fuel hoses restriction or clogging | Fuel injectors malfunction (Leakage or clogging, inoperative) | Fuel leakage from fuel system (including insulator, fuel injector O-ring) | Fuel filters restriction or clogging | CMP sensor is damaged (e.g. open or short circuit) | Camshaft is damaged | Improper air/fuel ratio mixture control | Exhaust system restriction or clogging | Catalytic converter malfunction | EGR system malfunction | Fuel-filler cap malfunction | EVAP control system malfunction | Fuel into evaporative purge hose | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Blown fuses | ||||||||||||||||||||
| 2 | Check engine light illuminates | X | X | X | |||||||||||||||||
| 3 | Will not crank | ||||||||||||||||||||
| 4 | Hard to start/long crank/erratic start/erratic crank | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||
| 5 | Engine stalls | After start/at idle | X | X | X | X | X | X | X | X | X | X | X | X | |||||||
| 6 | Cranks normally but will not start | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||
| 7 | Slow return to idle | ||||||||||||||||||||
| 8 | Engine runs rough/rolling idle | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||||
| 9 | Fast idle/runs on | ||||||||||||||||||||
| 10 | Low idle/stalls during deceleration | X | |||||||||||||||||||
| 11 | Engine stalls/quits | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | ||
| Engine runs rough | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||
| Misses | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||
| Buck/jerk | Acceleration/cruise/deceleration | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||
| Hesitation/stumble | Acceleration | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||
| Surges | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | |||
| 12 | Lack/loss of power | Acceleration/cruise | X | X | X | X | X | X | X | X | X | X | X | X | X | ||||||
| 13 | Knocking/pinging | Acceleration/cruise | X | X | X | X | |||||||||||||||
| 14 | Poor fuel economy | X | X | X | X | X | X | ||||||||||||||
| 15 | Emission compliance | X | X | X | X | X | X | X | X | X | X | X | X | X | |||||||
| 16 | High oil consumption/leakage | ||||||||||||||||||||
| 17 | Cooling system concerns | Overheating | |||||||||||||||||||
| 18 | Cooling system concerns | Runs cold | |||||||||||||||||||
| 19 | Exhaust smoke | X | X | X | X | X | X | X | X | ||||||||||||
| 20 | Fuel odor (in engine compartment) | X | X | X | X | X | |||||||||||||||
| 21 | Engine noise | X | |||||||||||||||||||
| 22 | Vibration concerns (engine) | ||||||||||||||||||||
| 23 | A/C does not work sufficiently | ||||||||||||||||||||
| 24 | A/C is always on or A/C compressor runs continuously | ||||||||||||||||||||
| 25 | A/C is not cut off under wide open throttle conditions | ||||||||||||||||||||
| 26 | Exhaust sulphur smell | X | X | X | X | X | |||||||||||||||
| 27 | Fuel refill concerns | ||||||||||||||||||||
| 28 | Fuel filling shut off concerns | ||||||||||||||||||||
| 29 | Spark plug condition | X | X | X | X | X | X | X | X | ||||||||||||
| 30 | ATX concerns | Upshift/downshift/engagement | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [FS5A-EL] .) | ||||||||||||||||||
X: Applied
| Troubleshooting item | Check valve (two-way) malfunction | PCV valve malfunction | Non-return valve malfunction | Fuel shut off valve malfunction | Constant voltage supply circuit malfunction | Nonreturn valve malfunction | Fuel shut off valve malfunction | Main relay malfunction (Mechanically or electrically) | PCM or sensor GND circuit open or short | ECT sensor malfunction | TR switch misadjustment (ATX) | TR switch malfunction (ATX) | Neutral switch or related circuit malfunction (MTX) | CPP switch or related circuit malfunction (MTX) | Brake switch or related circuit malfunction | MAP sensor or related circuit malfunction | A/F sensor, HO2S or related circuit malfunction | IAT sensor or related circuit malfunction | BARO sensor or related circuit malfunction | MAF sensor or related circuit malfunction | KS or related circuit malfunction | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Blown fuses | ||||||||||||||||||||||
| 2 | Check engine light illuminates | X | X | X | X | X | X | X | X | ||||||||||||||
| 3 | Will not crank | X | X | ||||||||||||||||||||
| 4 | Hard to start/long crank/erratic start/erratic crank | X | X | ||||||||||||||||||||
| 5 | Engine stalls | After start/at idle | X | X | |||||||||||||||||||
| 6 | Cranks normally but will not start | X | |||||||||||||||||||||
| 7 | Slow return to idle | X | |||||||||||||||||||||
| 8 | Engine runs rough/rolling idle | X | X | X | |||||||||||||||||||
| 9 | Fast idle/runs on | X | X | X | X | ||||||||||||||||||
| 10 | Low idle/stalls during deceleration | X | X | X | X | X | X | ||||||||||||||||
| 11 | Engine stalls/quits | Acceleration/cruise | X | X | X | X | X | X | X | ||||||||||||||
| Engine runs rough | Acceleration/cruise | X | X | X | X | X | X | X | |||||||||||||||
| Misses | Acceleration/cruise | X | X | X | X | X | X | ||||||||||||||||
| Buck/jerk | Acceleration/cruise/deceleration | X | X | X | X | X | X | ||||||||||||||||
| Hesitation/stumble | Acceleration | X | X | X | X | X | X | X | |||||||||||||||
| Surges | Acceleration/cruise | X | X | X | X | X | X | ||||||||||||||||
| 12 | Lack/loss of power | Acceleration/cruise | X | X | X | ||||||||||||||||||
| 13 | Knocking/pinging | Acceleration/cruise | X | X | X | X | |||||||||||||||||
| 14 | Poor fuel economy | X | X | ||||||||||||||||||||
| 15 | Emission compliance | X | X | ||||||||||||||||||||
| 16 | High oil consumption/leakage | X | |||||||||||||||||||||
| 17 | Cooling system concerns | Overheating | X | ||||||||||||||||||||
| 18 | Cooling system concerns | Runs cold | X | ||||||||||||||||||||
| 19 | Exhaust smoke | X | |||||||||||||||||||||
| 20 | Fuel odor (in engine compartment) | ||||||||||||||||||||||
| 21 | Engine noise | ||||||||||||||||||||||
| 22 | Vibration concerns (engine) | ||||||||||||||||||||||
| 23 | A/C does not work sufficiently | ||||||||||||||||||||||
| 24 | A/C is always on or A/C compressor runs continuously | ||||||||||||||||||||||
| 25 | A/C is not cut off under wide open throttle conditions | ||||||||||||||||||||||
| 26 | Exhaust sulphur smell | ||||||||||||||||||||||
| 27 | Fuel refill concerns | X | X | ||||||||||||||||||||
| 28 | Fuel filling shut off concerns | X | X | ||||||||||||||||||||
| 29 | Spark plug condition | X | X | X | |||||||||||||||||||
| 30 | ATX concerns | Upshift/downshift/engagement | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [FS5A-EL] .) | ||||||||||||||||||||
X: Applied
| Troubleshooting item | TP sensor or related circuit malfunction | APP sensor or related circuit malfunction | Improper refrigerant charging amount | Improper A/C system operation | A/C compressor magnetic clutch malfunction | Improper load signal input | ATX related parts malfunction (ATX) | Clutch slippage (MTX) | VSS related circuit malfunction | Improper ATF level (ATX) | Brake dragging | Low tire pressure | Loose parts | Improper balance of wheels and tires | Drive line malfunction | Suspension malfunction | Instrument cluster malfunction | Immobilizer system operating | Immobilizer system or related circuit malfunction | CAN communication error | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Blown fuses | |||||||||||||||||||||
| 2 | Check engine light illuminates | X | X | X | X | X | ||||||||||||||||
| 3 | Will not crank | X | X | |||||||||||||||||||
| 4 | Hard to start/long crank/erratic start/erratic crank | |||||||||||||||||||||
| 5 | Engine stalls | After start/at idle | X | X | X | X | X | X | ||||||||||||||
| 6 | Cranks normally but will not start | X | X | X | ||||||||||||||||||
| 7 | Slow return to idle | |||||||||||||||||||||
| 8 | Engine runs rough/rolling idle | X | X | X | ||||||||||||||||||
| 9 | Fast idle/runs on | X | X | X | ||||||||||||||||||
| 10 | Low idle/stalls during deceleration | X | X | X | X | X | X | X | X | |||||||||||||
| 11 | Engine stalls/quits | Acceleration/cruise | X | X | X | X | X | X | X | X | ||||||||||||
| Engine runs rough | Acceleration/cruise | X | X | X | X | X | X | X | X | |||||||||||||
| Misses | Acceleration/cruise | X | X | X | X | X | X | X | X | |||||||||||||
| Buck/jerk | Acceleration/cruise/deceleration | X | X | X | X | X | X | X | X | |||||||||||||
| Hesitation/stumble | Acceleration | X | X | X | X | X | X | X | X | |||||||||||||
| Surges | Acceleration/cruise | X | X | X | X | X | X | X | X | |||||||||||||
| 12 | Lack/loss of power | Acceleration/cruise | X | X | X | X | X | X | X | X | ||||||||||||
| 13 | Knocking/pinging | Acceleration/cruise | ||||||||||||||||||||
| 14 | Poor fuel economy | X | X | X | X | |||||||||||||||||
| 15 | Emission compliance | |||||||||||||||||||||
| 16 | High oil consumption/leakage | |||||||||||||||||||||
| 17 | Cooling system concerns | Overheating | X | X | X | |||||||||||||||||
| 18 | Cooling system concerns | Runs cold | X | X | ||||||||||||||||||
| 19 | Exhaust smoke | |||||||||||||||||||||
| 20 | Fuel odor (in engine compartment) | |||||||||||||||||||||
| 21 | Engine noise | X | X | |||||||||||||||||||
| 22 | Vibration concerns (engine) | X | X | X | X | |||||||||||||||||
| 23 | A/C does not work sufficiently | X | X | X | ||||||||||||||||||
| 24 | A/C is always on or A/C compressor runs continuously | X | X | |||||||||||||||||||
| 25 | A/C is not cut off under wide open throttle conditions | X | ||||||||||||||||||||
| 26 | Exhaust sulphur smell | |||||||||||||||||||||
| 27 | Fuel refill concerns | |||||||||||||||||||||
| 28 | Fuel filling shut off concerns | |||||||||||||||||||||
| 29 | Spark plug condition | |||||||||||||||||||||
| 30 | ATX concerns | Upshift/downshift/engagement | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [FS5A-EL] .) | |||||||||||||||||||
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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