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P0174: System too lean (Bank 2)
Fix soonSystem: Fuel and air
What P0174 means
The engine is getting too much air or too little fuel on bank 2.
Common symptoms
- Rough or unstable idle
- Hesitation or poor acceleration
- Worse fuel economy
- Loss of power
Common causes
- Vacuum or intake air leak
- Dirty or faulty mass air flow (MAF) sensor
- Weak fuel pump or clogged fuel filter
- Dirty or leaking fuel injector
- Exhaust leak near the sensor
Can I keep driving?
Fix soon. Usually drivable for a short time, but get it checked soon. Ignoring it can waste fuel, raise emissions and lead to more damage.
What to do next
- Write down the code and any symptoms you notice.
- Check the simple things first: the fuel cap, loose connectors and fluid levels where they apply.
- Do not just clear the code. If the light comes back, the cause is still there and needs a proper diagnosis.
- Read live data and freeze frame data with an OBD-II scanner app to see what the car was doing when the code was set.
Read P0174 from your own car
DriveHub connects to a $15 to $30 OBD-II adapter, reads the code from your car and explains it in plain English. iPhone and Android.
General information, not a diagnosis. Causes vary by make, model and engine. If you are unsure, have the car inspected.