Ignition System (DOHC) - General Information, Troubleshooting
GENERAL INFORMATION The ignition timing is controlled by the electronic engine control system. Optimum ignition timing values for all engine operating conditions are stored in the memory of the engine control module (ECM).
The engine operating conditions (crankshaft speed, load, engine temperature, etc.) are determined from the signals of various sensors. Based on the sensor signals and the optimum ignition timing data, the engine control module (ECM) sends signals to interrupt the current in the primary winding of the ignition coil.
High voltage is generated in the ignition coil to produce the spark, and thus the ignition timing is controlled.
TROUBLESHOOTING
| Symptom | Possible Cause | Remedy |
| The crankshaft is rotated by the starter, but the engine does not start or starts with difficulty. | Faulty ignition coil Faulty high-tension cables Faulty spark plugs Immobilizer malfunction Open or disconnected ignition system wiring | Replace the ignition coil Replace the high-tension cables Replace the spark plugs Adjust Inspect and replace |
| Rough idle or engine stalls | Faulty spark plugs Faulty ignition system wiring Faulty ignition coil Faulty high-tension cables | Replace the spark plugs Replace the wiring Replace the ignition coil Replace the high-tension cables |
| Inadequate engine response to accelerator pedal, poor acceleration (poor drivability) | Faulty spark plugs Faulty ignition system wiring | Replace the spark plugs Replace the wiring |
| Increased fuel consumption | Faulty spark plugs | Replace the spark plugs |
Test yourself
A quick Hyundai Elantra CN7 quiz: every answer comes with an explanation and a link to the manual page.