Honda Fault Code
Free · no signupP219A
Rough Idle / Rich Smell
Variant 1
System
Fuel System
Symptom
Rough Idle / Rich Smell
Diagnosis & fix steps
LOGIC: Air-Fuel Ratio Imbalance (Bank 1).
ACTION: Perform a cylinder contribution test; check for a leaking fuel injector.
Red Seal field insights
Logic: One cylinder is running much richer/leaner than the others.
FIX: On direct-injection models, this is a common "carbon buildup" or injector pintle fault.
Variant 2
System
Fuel System
Symptom
Rough Shaking Idle / Intermittent Surge
Diagnosis & fix steps
LOGIC: Bank 1 Air-Fuel Ratio Imbalance / Individual Cylinder Skew.
ACTION: Run an automated injector balance test using a scanner. Check for single cylinder vacuum leaks or isolated cylinder carbon loading.
Red Seal field insights
Advanced Tracking: The PCM monitors minute crankshaft speed changes for each distinct firing window. It isolates one cylinder that is tracking leaner than the rest.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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