z4- P0174 and P0171 errors - system to lean..help a lil'
- Thread starter van_gocea
- Start date
Since you have both codes it could be one of the following
MAF Sensor failed
Vacuum leak after the maf (check intake pipe)
Or more rarely since the codes are for both banks the primary lambda probes (in the cat)
Do you find that the revs on startup fluctuate before settling?
MAF Sensor failed
Vacuum leak after the maf (check intake pipe)
Or more rarely since the codes are for both banks the primary lambda probes (in the cat)
Do you find that the revs on startup fluctuate before settling?
Had these codes on my 2004 3 litre, no difference seen when driving, reset codes and after 70 miles EML back on again, had CCV and pipework replaced on specialist recommendation. 70 miles later EML back on, all air induction pipes ok. Changed MAF and all has been well since. Seems to be codes that are regularly thrown and list of possible faults is quite long if you search this and other BMW forums.
I too had these exact same codes, turned out to be the air intake bypass, smaller concertina like hose which tees onto the main manifold. It was quite difficult to spot as the split was on the narrower diameter section of the hose. £21 and 1/2 hour with the screwdrivers and job donevan_gocea said:
