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Fault code P0174 means mixture too lean (bank 2). Same meaning as P0171 but referring to the second bank: if it appears together with P0171 the cause is common.

Typical symptoms

• Rough idle
• Hesitation
• Engine light on

Most common causes

• Intake leaks common to both banks
• MAF sensor out of calibration
• Insufficient fuel pressure
• Faulty crankcase breather

How it is checked in diagnosis

• Comparing the corrections between the two banks
• Smoke test for intake leaks
• Checking fuel pressure

Can you drive with code P0174?

Yes, but the fault tends to get worse.

How MasterTuning helps

We read the real values from the ECU, not just the code: that is the difference between identifying the component responsible and replacing parts by trial and error. After the repair we clear the fault and check that it does not come back. Centres throughout Italy.

Read more: vehicle database · find an installer · what is ECU remapping

Do you have code P0174 on your car? Book a diagnosis at your nearest MasterTuning centre.

Frequently asked questions

What does fault code P0174 mean?

Code P0174 means mixture too lean (bank 2). Same meaning as P0171 but referring to the second bank: if it appears together with P0171 the cause is common.

Can you drive with fault P0174?

Yes, but the fault tends to get worse.

Is clearing code P0174 enough to fix it?

No: if the cause is still present the code comes back after a few kilometres. Clearing should only be done after the repair, with the diagnostic tool.

How much does it cost to fix code P0174?

It depends on the component responsible: the diagnosis is precisely what identifies it with real measurements, avoiding unnecessary replacements that cost far more than the correct repair.