Help Meeee!!! CEL from bad gas.

[bmwade]

I got some bad gas at a BP station. Fortunately I only got 3 gallons before I realized something was up with speed of the pump. I then added 15 gallons from a chevron station down the road, however the CEL had already come on the moment I turned the car on at the BP station. I ran through half a tank then added chevron additives and another half tank of good gas. I ran that tank empty then filled up again and cleared the codes. They stayed away for 2 days and a third of a tank. But it came back tonight on my way home.

here are the codes:
17544 - fuel trim bank 1: P1136 - system to lean - mil on
17546 - fuel trim bank 2: P1138 - system to lean - mil on

I'm stumped as to what to do.

[hahnmgh63]

Here is the Ross-Tech answer:
17544/P1136/004406 - Fuel Trim: Bank 1 (Add): System too Lean

Possible Solutions
Check Mass Air Flow (MAF) Sensor
Check Fuel Pressure Regulator
Check Fuel Pump
Check Intake/Exhaust System for Leaks
Check Secondary Air Injection for Leaks
Check Vacuum Lines for Leaks
Special Notes
Fuel Trim Info
When this fault is stored and external vacuum leaks are not found, less obvious problems may be present:
Check Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80)
Check Brake Booster and Hoses
Check Electric Vacuum Pump ( If Applicable )
Check Crankcase Ventilation System for faulty components. When the PCV or Crankcase Ventilation System is faulty, vacuum is typically present under the oil cap and misfire faults are common.