G
p0174
Moderate
GMC · Trucks
System Too Lean Bank 2
Quick Answer
Error code P0174 on your GMC Trucks means: System Too Lean Bank 2. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Faulty oxygen sensor on bank 2
  2. Vacuum leak
  3. Fuel injector malfunction
  4. Mass airflow sensor failure
  5. PCM programming issue
How to Fix It
1
Scan vehicle with diagnostic tool
2
Inspect bank 2 oxygen sensor
3
Check for vacuum leaks using smoke test
4
Verify fuel injector pulse
5
Test mass airflow sensor functionality
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
Vacuum hose
Fuel injector
MAF sensor
Related Error Codes
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