Severity: Fix within days. Drive with caution and watch for new symptoms.
The engine is getting too much fuel or too little air on bank 1, so the exhaust has less oxygen than it should. The computer has already cut as much fuel as it can to compensate.
Check fuel pressure and injectors for leaks, clean the mass air flow sensor, and test the oxygen sensor.
Expect black exhaust smoke, a fuel smell, and poor fuel economy. Drivable with care, but it can foul spark plugs and damage the catalytic converter over time.
You can drive short distances carefully; watch for worsening symptoms. Expect black exhaust smoke, a fuel smell, and poor fuel economy. Drivable with care, but it can foul spark plugs and damage the catalytic converter over time.
The most common causes are: Leaking fuel injector; High fuel pressure; Dirty mass air flow sensor; Failing oxygen sensor; Stuck-open thermostat keeping the engine cold; Clogged air filter. A scan tool and a visual check of the parts above is where a technician starts.
Check fuel pressure and injectors for leaks, clean the mass air flow sensor, and test the oxygen sensor.
