P0174 Chevrolet Tahoe
System Too Lean (Bank 2) · Powertrain Code · High · Repair: Moderate
What is P0174?
The engine is running lean on bank 2. Same causes as P0171 but affecting the opposite cylinder bank on V-engines.
When the Chevrolet Tahoe triggers code P0174 (system too lean (bank 2)), it typically points to an issue in the powertrain system. This is a high severity code, so address it promptly to avoid further damage or safety concerns. Below you'll find the most common causes, symptoms, and repair options specific to the Chevrolet Tahoe.
This repair is rated moderate, meaning some experience and specialty tools required.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Chevrolet Tahoe.
Common Causes on Chevrolet Tahoe
- Intake manifold gasket leak on bank 2 of 5.3L, 6.2L, or 3.0L Duramax
- Cracked vacuum hose on passenger side valve cover
- Bank 2 fuel injector failure or restricted flow
- AFM/DFM oil consumption causing fouled bank 2 spark plugs and lean condition
- Mass airflow sensor drift on high-mileage engines
Symptoms
- Rough idle especially when cold
- Hesitation or stumble on acceleration
- Engine surging at steady throttle
- Lean misfire under load
- Poor fuel economy
- Check engine light illuminated
Notes for Chevrolet Tahoe
Tahoe, Suburban, and Yukon V8 engines commonly develop bank 2 lean conditions from intake gasket leaks. Often appears with P0171.