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p0171 meaning
P0171: System Too Lean (Bank 1)
Fuel trim has exceeded the lean limit. Possible causes include…
Forum · 14 replies
It’s the O2 sensor.
Definitely a vacuum leak.
Just clear the code.
Repair estimate#2041
MAF sensor replacement
Fuel system service
Intake inspection
Do I need all this?Approve all
2019 CX-5 · 48,210 mi
IGNITION SYNC
IGNITION SYNCCheck engine light · P0171
A fuel mixture may be too lean
The engine is getting more air than expected. Usually a small leak, not an emergency.
Vacuum leakMost likely
Aging MAF sensorPossible
Loose intake hoseLess likely
Next up · in about 1,800 mi
Engine air filter
How urgent
Book service in the next few days
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New request8:14 AM
2019 Mazda CX-5
Check engine · P0171 · 3 photos
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