Ignition system diagnostics
Faulty ignition causes misfiring, jerks under acceleration, difficult starting and increased fuel consumption; over time it damages the catalytic converter because unburned fuel burns inside it.
Symptoms
- Misfiring, jerking on acceleration, hard starting, and higher fuel consumption.
What's included
- We check the entire chain: spark plugs, coils, high-voltage leads, signals from the crankshaft and camshaft sensors, and ignition timing in live data. A scanner tracks misfires cylinder by cylinder, showing which cylinder is operating incorrectly. We then swap the coil and plug to determine the exact cause. This approach makes it possible to replace one part rather than a whole set and confirm that the problem has been resolved.
Additional checks
- Condition of spark plugs, coils and high-voltage leads
- Crankshaft and camshaft sensor signals
- Ignition timing in live data
Why it matters
Unburned fuel damages the catalytic converter over time, so misfires are tracked cylinder by cylinder with a scanner. Swapping a coil and plug between cylinders lets a single part be replaced instead of the whole set.
More details
Faulty ignition shows up as a rough idle (misfiring), jerking on acceleration, hard starting, and increased fuel consumption, and over time it kills the catalytic converter — unburned fuel finishes burning inside it. We check the whole chain: spark plugs, coils, high-voltage wires, crankshaft and camshaft sensor signals, and ignition timing in the live data. We track misfires per cylinder with the scanner — this shows exactly which cylinder is running incorrectly. Then, by swapping the coil and the spark plug, we pin down the exact cause. This approach lets us replace a single part instead of a whole set and know for certain that the problem is fixed.
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