P0174Mclaren P1Years: 1996 - 2026
System Too Lean (Bank 2)
Reviewed by ASE Certified Technician
What does this mean?
Code P0174 indicates the fuel system on Bank 2 is running too lean. Same diagnostic approach as P0171 but affecting the opposite bank of cylinders.
Disclaimer: This diagnostic code is part of the standard OBD2 system and can apply to Mclaren P1 models manufactured from 1996 to 2026. However, please note that the presence of this specific code depends on your vehicle's exact engine configuration, options, and production year.
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Common Causes
Vacuum leak in intake system
Dirty or contaminated MAF sensor
Weak or failing fuel pump
Clogged fuel filter
Faulty fuel pressure regulator
Clogged or faulty fuel injector
Intake manifold gasket leak
Exhaust leak before oxygen sensor
Faulty oxygen (O2) sensor
Symptoms to Watch For
- Check Engine Light is illuminated
- Rough or unstable idle
- Hesitation or stumble during acceleration
- Poor acceleration or sluggish response
- Engine stalling or dying unexpectedly
- Decreased fuel economy