P01D1
Cylinder 4 Injection Timing Performance Over Retarded
Generic OBD-II
Common symptoms
What you'll notice
- Check the fuel injector for clogging or malfunctioning
- Inspect the ignition system for faulty spark plugs or ignition coil related issues
- Verify the timing belt or chain for proper tension and alignment
- Ensure the engine control module (ECM) is functioning correctly and consider reprogramming or replacing if necessary
Common causes
Most likely first
- Faulty fuel injector in cylinder 4
- Malfunctioning engine control module (ECM)
- Restricted fuel supply to cylinder 4
- Ignition timing issue in cylinder 4
- Low compression in cylinder 4
How to diagnose & fix
Work through it in order
- Engine misfires or runs rough
- Decreased acceleration or lack of power
- Increased fuel consumption
- Rough idle or stalling
- Check Engine Light illuminates
Read & clear P01D1 yourself
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