Rich at idle bank 1.
Common symptoms
- Rough idle
- Fuel smell
- P0172
Typical causes
- Leaking injector at idle
- Stuck open purge valve
- MAF dirty reading low air
What scanner do you need?
Enhanced OBD2 scanner (live data graphs, freeze frame, battery voltage test)
Use live data and freeze frame to confirm the fault before replacing parts. ABS, SRS, and network U-codes usually require a full-system scanner.
Diagnostic tips
- Record freeze frame data when the code first sets
- Clear the code only after fixing the root cause
- Check for related pending codes that point to a common issue
- Verify battery voltage is above 12.4V before chasing sensor codes