P1091 SUBARU Possible Causes
- Faulty tumble generator
- Tumble generator harness is open or shorted
- Poor electrical connection in tumble generator circuit
How to Fix P1091 SUBARU Code?
Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
Check Engine Light On (or Service Engine Soon Warning Light)
P1091 SUBARU Meaning
The tumble generator system uses an electronically controlled throttle valve in each intake port.
During cold idle, the tumble generator system will redirect the air charge through another port. These ports have a finishing characteristic that causes the air/fuel mixture to swirl and tumble considerably, creating better combustion. This results in improved idle quality, cleaner emissions, and easier cold starts.
Once the vehicle is warmed up, the tumble generator system will be disabled, and the intake air charge will be directed through the standard intake ports.
The Diagnostic Trouble Code (DTC) sets when the tumble generator valve is detected closed when the desired position is open.