System Too Rich (Bank 2)

Bank 2 (passenger side) running rich. On EcoBoost engines, check for leaking fuel injectors on Bank 2 using a fuel injector balance test. Also check the MAF sensor for contamination from oiled air filters. A cracked intercooler or leaking charge pipe causes incorrect boost readings that make the ECU add too much fuel. Clean the MAF with CRC MAF cleaner.

Bank 2 rich on the 5.4L V8. Check for a leaking fuel pressure regulator -- sniff or look for fuel in the vacuum line connected to the regulator. Also check the Bank 2 upstream O2 sensor for contamination from coolant (cracked intake manifold). A stuck-open EVAP purge valve can also cause rich on both banks. Clean the MAF sensor first.

Bank 2 system too rich. Check the EVAP purge solenoid (ACDelco) for sticking open -- this dumps fuel vapor into the intake causing a rich condition. Command the purge valve closed with a scan tool and monitor fuel trims. Also check for a leaking Bank 2 fuel injector. On AFM-equipped engines, excessive oil consumption can foul the Bank 2 O2 sensor. Confirm the exact part for your year and engine with a retailer's fitment lookup or your VIN before ordering - these applications split by engine and build date.

Bank 2 running rich on the Hemi. Check for a cracked passenger side exhaust manifold first -- exhaust leaks cause the O2 sensor to read incorrectly, and the ECU compensates by adding fuel. If no exhaust leak, check fuel injector spray pattern and MAF sensor accuracy. Clean the MAF sensor with CRC MAF cleaner as a first step.