Limp Mode no codes

gaaldaco · 02-06-2023, 08:21 PM

Hello,

I'm new to the N54 engine but ran into an issue that i may think is a boost leak or something completely different, Car was fine under normal load but recently i did a pull and after the pull the car went into what i can only describe as a limp mode, No light, no codes. Shutting off the car then turning back on fixed the issue but it's only gotten worse now it goes into limp mode just by giving it a little gas. I will say that the belt did break and i am not able to do anymore pulls but if this is just a belt issue then i will find out soon enough. Any insight will help thank you.https://datazap.me/u/gaaldaco/log-16...og=0&data=3-21

Houranimd49 · 02-06-2023, 10:20 PM

So, you’re able to drive the car but the belt broke? This doesn’t make sense.

Based on what you’re saying otherwise plus the data log, looks like a potential boost leak. Lots of plastic in that engine bay that can and likely will deteriorate if it already hasn’t. Take a look around carefully for any broken plastic pipes or even minor/major cracks first.

gaaldaco · 02-06-2023, 10:55 PM

The belt just broke, I was going to do one more pull but I looked before I pulled out of my driveway and it was starting to tear badly. I’m sure a weak belt wouldn’t be the culprit of this. Engine is clean all gaskets have been replaced oil was coming from the housing so I’m guessing that’s what ripped the belt off but I’m replacing that again. Oil level is fine along with pressure. Again no codes pop up either.

Houranimd49 · 02-06-2023, 11:01 PM

Sorry boss I read your original post too quickly. I’m still convinced there is a potential boost leak hiding somewhere. Another suggestion is to get Bimmerlink and see if there are any hidden codes (I.e would not cause an engine light) that could explain what’s going on.

BoostleakTV · 02-07-2023, 09:02 AM

Not so sure about a boost leak.. as far as I can see he’s not logging target parameters.. so from the log there is no way to tell - how did you come to the boost leak conclusion?

What I do see is fuel rail psi taking a huge dip during your pull. OP, you running ethanol on an OTS map?

gaaldaco · 02-07-2023, 03:51 PM

Everything dipped when I let off and hit the brake and then tried to get back on again, not good logs I know but I could only run two before the belt broke.

gaaldaco · 02-07-2023, 04:37 PM

Also I’m not sure why target parameters aren’t showing but all those are normal as well throughout the pull. Including when it goes into the “limp mode” the actual is always around the target.

gaaldaco · 02-10-2023, 07:08 PM

Just for anyone having this same issue, I went to a normal stage 2+ tune, no extras and it fixed the issue. I believe the ecu was protecting the car still don’t know what setting did it but we’ll see in the summer

02-06-2023, 08:21 PM	#1
gaaldaco New Member 0 Rep 5 Posts Drives: bmw 135i Join Date: Feb 2023 Location: Michigan iTrader: (0)	Limp Mode no codes Hello, I'm new to the N54 engine but ran into an issue that i may think is a boost leak or something completely different, Car was fine under normal load but recently i did a pull and after the pull the car went into what i can only describe as a limp mode, No light, no codes. Shutting off the car then turning back on fixed the issue but it's only gotten worse now it goes into limp mode just by giving it a little gas. I will say that the belt did break and i am not able to do anymore pulls but if this is just a belt issue then i will find out soon enough. Any insight will help thank you.https://datazap.me/u/gaaldaco/log-16...og=0&data=3-21
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02-06-2023, 10:20 PM	#2
Houranimd49 First Lieutenant 252 Rep 333 Posts Drives: F10 535i xDrive, F25 xDrive35i Join Date: Apr 2019 Location: MI iTrader: (0) Garage List 2012 BMW X3 xDriv ... [9.25] 2011 BMW 535i xDrive [9.50]	So, you’re able to drive the car but the belt broke? This doesn’t make sense. Based on what you’re saying otherwise plus the data log, looks like a potential boost leak. Lots of plastic in that engine bay that can and likely will deteriorate if it already hasn’t. Take a look around carefully for any broken plastic pipes or even minor/major cracks first.
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02-06-2023, 10:55 PM	#3
gaaldaco New Member 0 Rep 5 Posts Drives: bmw 135i Join Date: Feb 2023 Location: Michigan iTrader: (0)	The belt just broke, I was going to do one more pull but I looked before I pulled out of my driveway and it was starting to tear badly. I’m sure a weak belt wouldn’t be the culprit of this. Engine is clean all gaskets have been replaced oil was coming from the housing so I’m guessing that’s what ripped the belt off but I’m replacing that again. Oil level is fine along with pressure. Again no codes pop up either.
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02-06-2023, 11:01 PM	#4
Houranimd49 First Lieutenant 252 Rep 333 Posts Drives: F10 535i xDrive, F25 xDrive35i Join Date: Apr 2019 Location: MI iTrader: (0) Garage List 2012 BMW X3 xDriv ... [9.25] 2011 BMW 535i xDrive [9.50]	Sorry boss I read your original post too quickly. I’m still convinced there is a potential boost leak hiding somewhere. Another suggestion is to get Bimmerlink and see if there are any hidden codes (I.e would not cause an engine light) that could explain what’s going on.
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02-07-2023, 09:02 AM	#5
BoostleakTV Enlisted Member 20 Rep 40 Posts Drives: 2015 BMW 335i, 2020 Supra Join Date: Jan 2023 Location: US iTrader: (0)	Not so sure about a boost leak.. as far as I can see he’s not logging target parameters.. so from the log there is no way to tell - how did you come to the boost leak conclusion? What I do see is fuel rail psi taking a huge dip during your pull. OP, you running ethanol on an OTS map?
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02-07-2023, 03:51 PM	#6
gaaldaco New Member 0 Rep 5 Posts Drives: bmw 135i Join Date: Feb 2023 Location: Michigan iTrader: (0)	Everything dipped when I let off and hit the brake and then tried to get back on again, not good logs I know but I could only run two before the belt broke.
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02-07-2023, 04:37 PM	#7
gaaldaco New Member 0 Rep 5 Posts Drives: bmw 135i Join Date: Feb 2023 Location: Michigan iTrader: (0)	Also I’m not sure why target parameters aren’t showing but all those are normal as well throughout the pull. Including when it goes into the “limp mode” the actual is always around the target.
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02-10-2023, 07:08 PM	#8
gaaldaco New Member 0 Rep 5 Posts Drives: bmw 135i Join Date: Feb 2023 Location: Michigan iTrader: (0)	Just for anyone having this same issue, I went to a normal stage 2+ tune, no extras and it fixed the issue. I believe the ecu was protecting the car still don’t know what setting did it but we’ll see in the summer
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