1999 Mazda Protege 1.6L with engine code P0171

Question

What is the cause? I just had my clutch kit put in at a shop. Do you think they forgot to connect a hose back, or could they have damaged a sensor.?

Answer 1

P0171 Fuel trim lean Bank 1

This code is not a sensor , but a condition of the engine, more than anything something is not secure, in order to replace the cluch the MAF air duct would be removed, if that is not secure properly this code would set, a recheck of the vacuum hose may just be the soultion

Answer 2

P0171 MAZDA Code - Lean Air/Fuel Ratio Bank 1
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