Spark Plug Fault (Missing Event)
Indicates a fault in the ignition system where the spark plug did not ignite the air-fuel mixture as expected.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer is saying that the spark plug failed to fire properly, which means the engine might not be running smoothly or could stall.
What the computer is actually seeing
The Engine Control Module (ECM) monitors the ignition events across the cylinders. If a spark plug doesn't fire at the proper time (about 1-3 milliseconds after the piston hits top dead center), it sees an anomaly and triggers the fault code.
What a healthy reading looks like
Expected ignition event in all cylinders should occur every 5-6 milliseconds, under normal operating conditions.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the engine wiring and connectors connected to the ignition system for any signs of wear or damage. Decision: If damaged, repair it; if okay, move to step 2.
- 22. Test the spark plugs for proper resistance (should be about 5k-10k ohms) and check for wear. Decision: If worn or damaged, replace spark plugs; if okay, move to step 3.
- 33. Inspect the ignition coils for proper operation. Check primary voltage (should be around 12v) and secondary voltage (should be around 20k-40k volts during operation). Decision: If coils fail to meet specs, replace coils; if okay, move to step 4.
- 44. Check the air-fuel mixture using a scan tool or data parameters. Ensure the Fuel Rail Pressure is within normal range (typically 40-60 psi). Decision: If mixture is too lean or too rich, adjust; if normal, check the ECM settings.
Common causes
- Faulty spark plug
- Wiring issues to the ignition coil
- Faulty ignition coil
- Air-fuel mixture problems
- Weak battery supply to ignition system
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Moderate severity indicates drivability may be impacted; fix soon to avoid stalling or rough running.
Will this code clear itself?
It may clear once the fault is resolved and the system detects normal operation.
Why does it pair with other SPNs?
Related SPNs often indicate interconnected issues with the ignition system or air-fuel management.
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