p2177
Moderate
Mazda · Sedans
System Too Lean Off Idle Bank 1
Quick Answer
Error code P2177 on your Mazda Sedans means: System Too Lean Off Idle Bank 1. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Test oxygen sensor voltage and switching
2
Perform fuel pressure test at idle
3
Inspect for vacuum leaks
4
Check fuel injector spray pattern
5
Clean or replace mass air flow sensor
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 injectors
Fuel pump
MAF sensor
Related Error Codes