What does code P0174 mean on a BMW and is it safe to drive?
P0174: System Too Lean (Bank 2). Here's what it means on your BMW, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
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What this code means
Same as P0171 but for bank 2. The engine is running too lean on the side that contains cylinder 2.
Common causes for your BMW
- Vacuum leaks affecting bank 2
- Faulty MAF or O2 sensor
- Fuel delivery issues
Symptoms
- Check Engine Light
- Rough idle, hesitation
- May appear with P0171 on V6/V8 engines
Typical fixes
- Smoke test for vacuum leaks
- Inspect intake gaskets and hoses
- Check fuel pressure and filter
Repair cost range
For a BMW, repairs for P0174 often fall between $100 and $600, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on BMW
BMW N52/N54 P0174 alongside P0171 is a strong indicator of a cracked intake boot or CCV failure affecting all cylinders. Inspect both the main intake boot and the small idle hoses before further diagnosis.
Most commonly affected models
3 Series 2006–20125 Series 2007–2013