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.
Symptom Troubleshooting Index
These symptoms DO NOT trigger diagnostic trouble codes (DTCs) or cause the malfunction indicator lamp (MIL) to come on. If the MIL is reported on, check for DTCs. If the vehicle has one of these symptoms, do the diagnostic procedure for it, in the sequence listed, until you find the cause.
| Symptom | Diagnostic procedure | Also check for |
|---|---|---|
| Engine will not start (MIL works OK, no DTCs set) |
|
|
| Engine will not start (MIL comes on and stays on, or never comes on at all, no DTCs set) | Troubleshoot the MIL circuit (see MIL CIRCUIT TROUBLESHOOTING ). | Β |
| Engine will not start (immobilizer indicator stays on or flashes) | Troubleshoot the immobilizer system (see HID BULB REMOVAL ). | Β |
| Engine is hard to start (MIL works OK, no DTCs set) |
|
|
| Cold fast idle too low (MIL works OK, no DTCs set) |
|
Β |
| Cold fast idle too high (MIL works OK, no DTCs set) |
|
Β |
| Idle speed fluctuates (MIL works OK, no DTCs set) |
|
Intake air leaks |
| After warming up, idle speed is below specification without load (MIL works OK, no DTCs set) |
|
Faulty throttle cable |
| After warming up, idle speed is above specification without load (MIL works OK, no DTCs set) |
|
Β |
| Low power (MIL works OK, no DTCs set) |
|
|
| Engine stalls (MIL works OK, no DTCs set) |
|
|
| Difficult to refuel (MIL works OK, no DTCs set) |
|
Malfunctioning gas station filling nozzle. |
| Fuel overflows during refueling (No DTCs set) | Replace the fuel tank vapor control valve (see FUEL TANK VAPOR CONTROL VALVE REPLACEMENT ). | Malfunctioning gas station filling nozzle. |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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