P1150 Lack of Upstream HO2S Switch - Adaptive Fuel at Limit (Bank 2)

What does P1150 mean on a Ford?

P1150 — Lack of Upstream HO2S Switch - Adaptive Fuel at Limit (Bank 2). This Ford-enhanced code applies to F-150, Mustang, Expedition, Explorer with V6 and V8 engines.

Common causes of P1150

• Fuel trims maxed out by a bank 2 lean or rich fault
• Slow bank 2 upstream oxygen sensor
• Bank 2 vacuum leak or injector fault
• Exhaust leak ahead of the bank 2 sensor
• Sensor contamination

How to fix P1150

1. Read bank 2 long-term trims to find the correction direction
2. Repair the underlying fuel or air fault first
3. Inspect the bank 2 exhaust for leaks
4. Check sensor switching speed
5. Replace the bank 2 upstream sensor after trims normalize