P2194
System Too Rich at Higher Load (Bank 2)
Bank 2 fuel trim hits the rich limit only at higher load. Often excessive fuel pressure, a stuck-closed MAF reading low, or coolant temperature signal stuck cold causing over-fuelling.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Increased fuel consumption
- Black smoke from exhaust on acceleration
- Smell of unburned fuel, fouled spark plugs
Common causes
Ordered by how often each turns out to be the cause.
- Fuel pressure too highCommon
- MAF reads low under loadPossible
Parts involved
- Fuel Pressure Regulator
- Mass Air Flow Sensor
- Coolant Temperature Sensor
P2194 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.