Bmw 04 325i stalling after a hour
Asked by Fmlbmw Jul 29, 2020 at 04:03 PM about the 2004 BMW 3 Series 325i Sedan RWD
Question type: Maintenance & Repair
My car runs fines but after a hour of driving it stall but will crank but up just
stall again but I can get it to stay crank and floor it it driving where I need it
unless it come to a stop only does after a hour of driving codes are p0456
p0430 p04420 p0174 and p0171
3 Answers
P0171 and P0174 is a lean condition indicating a vacuum leak. Smoke test the car to find it. Most likely it's time to replace your air inlet hoses if they are original. P0456 is a EVAP leak. the P0420 and 430 are O2 catalyst codes. So I would tackle the vacuum and evap leaks first and then hope the O2 codes go away. Also check your fuel pressure, it sounds like you might have a soft fail fuel pump. Replace the fuel filter if you haven't yet and it is original. It is under a panel under the driver door. Plenty of DIY's out there just search. Use BMW E46 DIY and the procedure.
Your catalytic convertors might also be clogging from past misfires and other issues not attended to as soon as they crop up. Have a muffler shop check the back pressure to confirm.
Tried smoke test nothing change dmtl last week now changing crank breather case in the am but will check the muffler and fill filter as tomorrow
