System Too Lean at Idle Bank 1

The engine is running too lean (too little fuel, too much air) when idling on the cylinder #1 side of the engine, which can cause rough idle and hesitation. This is typically caused by a vacuum leak, weak fuel pump, faulty oxygen sensor, or dirty fuel injector. Poor idle quality and reduced engine power may be noticed by the driver.

No detailed repair guide linked yet. Check back soon or search for related issues.