Drivetrain malfunction issue with cats and possible vacuum leak ?

delaineyklein · 06-15-2023, 05:16 PM

2014 435i awd 90k miles - VRSF chargepipe, VRSF high-flow cat, Dinan cold air intake, Dinan sport performance tuner

I installed the high-flow cat back in February. It’s thrown a few codes but overall hasn’t been giving me any issues. My dad wouldn’t let me “tune” the car so I haven’t been able to code it in.

Recently, I got in contact with a mechanic to figure out how to clear the codes so it would pass inspection. He recommended disconnnecting and reconnecting the battery to attempt to reset the system, which I did. The check engine came back on but the car ran fine for 2+ weeks. Did a few pulls on the highway a couple days ago. The car went into limp mode the next day and threw emissions and cat deficiency codes (both new).

P00BD
P0420
P0440 (new)
P10F3 (new)
P112F
P12A5
P12A8
P12A9
P12B9 (new)

I’ve read on other forums that the Dinan intake has issues and could be the cause for P12A5 and P12A9. Let me add that I accidentally touched one of the two sensors in the cat during the install, which is probably causing P0420.

Not sure if it just has a vacuum leak and needs a tune or if it’s something else. Thanks!

BMWILUVU · 06-15-2023, 08:39 PM

Are you really trying to pass inspection with all that? I would revert to stock for the inspection. As far as the laundry list, start with cleaning the MAF sensor and clean the gasket for your fuel cap and get your evap going cause it takes a looong while to green-light.

thejeremyman9 · 06-16-2023, 11:45 AM

You cant disconnect the battery to pass inspection because although it will clear codes, it also resets your monitors. As you go through the drive cycle to get monitors ready, the codes will come back. It simply doesnt work that way.

If you need your cat monitor ready, VRSF DP isnt going to work, so you will need to swap back to stock. The dinan intake can, but not always, causes MAF codes. I dont know all those codes by memory but if you have to pass inspection anyways you might as well revert back to stock DP and intake, remove the dinan piggyback, and see if all the codes go away. You can keep the VRSF CP installed and confirm it does not have any leaks. Then after passing inspection install one at a time to confirm you do not introduce any problems.

You dont "code in" downpipes or other hardware mods. The only thing the tune can do is disable the CEL but your monitor would still not be ready.

06-15-2023, 05:16 PM	#1
delaineyklein New Member 60 Rep 13 Posts Drives: 2014 BMW 435i xdrive Join Date: Jun 2023 Location: Pennsylvania iTrader: (0) Garage List 2014 BMW 435i [9.00]	Drivetrain malfunction issue with cats and possible vacuum leak ? 2014 435i awd 90k miles - VRSF chargepipe, VRSF high-flow cat, Dinan cold air intake, Dinan sport performance tuner I installed the high-flow cat back in February. It’s thrown a few codes but overall hasn’t been giving me any issues. My dad wouldn’t let me “tune” the car so I haven’t been able to code it in. Recently, I got in contact with a mechanic to figure out how to clear the codes so it would pass inspection. He recommended disconnnecting and reconnecting the battery to attempt to reset the system, which I did. The check engine came back on but the car ran fine for 2+ weeks. Did a few pulls on the highway a couple days ago. The car went into limp mode the next day and threw emissions and cat deficiency codes (both new). P00BD P0420 P0440 (new) P10F3 (new) P112F P12A5 P12A8 P12A9 P12B9 (new) I’ve read on other forums that the Dinan intake has issues and could be the cause for P12A5 and P12A9. Let me add that I accidentally touched one of the two sensors in the cat during the install, which is probably causing P0420. Not sure if it just has a vacuum leak and needs a tune or if it’s something else. Thanks!
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06-15-2023, 08:39 PM	#2
BMWILUVU Lieutenant Colonel 809 Rep 1,597 Posts Drives: 340ix Join Date: Mar 2017 Location: The Boibs iTrader: (0)	Are you really trying to pass inspection with all that? I would revert to stock for the inspection. As far as the laundry list, start with cleaning the MAF sensor and clean the gasket for your fuel cap and get your evap going cause it takes a looong while to green-light.
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06-16-2023, 11:45 AM	#3
thejeremyman9 Major General 4374 Rep 7,622 Posts Drives: 2015 BMW 335i Join Date: May 2019 Location: Cali iTrader: (0)	You cant disconnect the battery to pass inspection because although it will clear codes, it also resets your monitors. As you go through the drive cycle to get monitors ready, the codes will come back. It simply doesnt work that way. If you need your cat monitor ready, VRSF DP isnt going to work, so you will need to swap back to stock. The dinan intake can, but not always, causes MAF codes. I dont know all those codes by memory but if you have to pass inspection anyways you might as well revert back to stock DP and intake, remove the dinan piggyback, and see if all the codes go away. You can keep the VRSF CP installed and confirm it does not have any leaks. Then after passing inspection install one at a time to confirm you do not introduce any problems. You dont "code in" downpipes or other hardware mods. The only thing the tune can do is disable the CEL but your monitor would still not be ready.
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