P219A GMC – Fuel Trim Cylinder Balance Bank 1

P219A GMC Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light),Excessive Fuel Consumption

P219A GMC Possible Causes

Leaking or contaminated fuel injectors,Low fuel pressure or running out of fuel,Leaking evaporative emission (EVAP) canister purge valve,Exhaust or intake air system leaks,Exhaust gas recirculation (EGR) system,Positive crankcase ventilation (PCV) system is leaking or the valve is stuck open,Ignition system,Incorrectly seated engine oil dipstick, tube or oil fill cap

P219A GMC Description

The Fuel Trim Cylinder Balance diagnostic detects a rich or lean cylinder to cylinder air/fuel ratio imbalance in each bank. The diagnostic monitors the pre-catalyst heated oxygen sensor (HO2S) signal’s frequency and amplitude characteristics by calculating an accumulated voltage over a predetermined sample period. An imbalance is indicated when multiple samples of the accumulated voltage are consistently higher than the desired value.