Cylinder 1 Misfire Detected
The engine control module has detected that cylinder #1 is misfiring, meaning it's not igniting fuel properly or inconsistently. This reduces engine power, increases emissions, and can damage the catalytic converter if left unaddressed.
What You Might Notice
- Rough idle or engine stumbling
- Loss of power during acceleration
- Difficulty starting the engine
- Increased fuel consumption
- Check engine light illuminated
Most Common Causes
- 1
Faulty spark plug or ignition wire
Worn, fouled, or degraded spark plugs or high-voltage ignition wires prevent proper spark generation in cylinder #1.
- 2
Faulty ignition coil pack
A defective coil pack fails to produce sufficient spark voltage to ignite the air-fuel mixture in cylinder #1.
- 3
Fuel injector malfunction
A clogged, leaking, or electrically faulty fuel injector in cylinder #1 delivers incorrect fuel quantity or timing.
- 4
Low compression or mechanical damage
Worn piston rings, valve damage, or head gasket failure reduces compression pressure in cylinder #1, preventing proper combustion.
How to Diagnose It
- 1
Check Faulty spark plug or ignition wire — Worn, fouled, or degraded spark plugs or high-voltage ignition wires prevent proper spark generation in cylinder #1.
- 2
Check Faulty ignition coil pack — A defective coil pack fails to produce sufficient spark voltage to ignite the air-fuel mixture in cylinder #1.
- 3
Check Fuel injector malfunction — A clogged, leaking, or electrically faulty fuel injector in cylinder #1 delivers incorrect fuel quantity or timing.
- 4
Check Low compression or mechanical damage — Worn piston rings, valve damage, or head gasket failure reduces compression pressure in cylinder #1, preventing proper combustion.
How to Fix It
- 1
Replace spark plug and inspect ignition wire
Remove and inspect the spark plug in cylinder #1. Replace if worn, fouled, or damaged. Check the ignition wire for cracks or corrosion and replace if necessary.
- 2
Test and replace ignition coil pack
Test the coil pack serving cylinder #1 with a multimeter for proper resistance and output voltage. Replace the coil pack if it fails testing.
- 3
Clean or replace fuel injector
Use a fuel injector cleaner additive or have the injector professionally cleaned. If cleaning fails, have the fuel injector tested and replaced if necessary.
- 4
Perform compression test and inspect cylinder head
Perform a cylinder compression test to check for low compression in cylinder #1. If compression is low, inspect for burned valves, worn rings, or head gasket leaks and repair accordingly.
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