P03C5
Cylinder 5 Pressure Variation High
Generic OBD-II
Common symptoms
What you'll notice
- Check and replace faulty spark plugs in cylinder 5
- Check and clean fuel injectors for cylinder 5
- Inspect and replace ignition coil for cylinder 5
- Perform a compression test and evaluate cylinder 5's compression level
Common causes
Most likely first
- Faulty fuel injector in cylinder 5
- Ignition system malfunction in cylinder 5
- Vacuum leak in cylinder 5
- Low compression in cylinder 5
- Faulty Engine Control Module (ECM) for cylinder 5
How to diagnose & fix
Work through it in order
- Rough or uneven engine idle
- Engine misfires or hesitation during acceleration
- Decreased engine performance or power
- Increased fuel consumption
- Check engine light or warning indicator illuminated
Read & clear P03C5 yourself
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