p1148
Moderate
Infiniti · SUVs
Closed Loop Fueling Not Achieved (Bank 2)
Quick Answer
Error code P1148 on your Infiniti SUVs means: Closed Loop Fueling Not Achieved (Bank 2). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Faulty oxygen sensor
  2. Air leak in intake manifold
  3. Fuel pressure too high or low
  4. Fuel injector stuck
  5. ECM calibration issue
How to Fix It
1
Check oxygen sensor heater circuit
2
Measure fuel pressure at fuel rail
3
Inspect for intake vacuum leaks
4
Test fuel injector pulse width
5
Replace oxygen sensor if needed
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Oxygen sensor
Fuel pressure gauge
Vacuum hose
Fuel injector cleaner
Related Error Codes
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