catless downpipe throwing cel even with jb4?

nazzri · 01-19-2023, 06:54 AM

Featured on BIMMERPOST.com

Hey guys had the engine light for a while, got told if I get jb4 it’ll get rid of it. I have the jb4 and the engine light came back the next day. Is there anything I can do to stop it from coming on?

mike@x-ph.com · 01-19-2023, 09:05 AM

What you were told was, unfortunately, not accurate.

The JB4 does not hide the check engine light.

I recommend you invest in a downpipe that does not trigger the check engine light; Active Autowerks catted is the best.

Skyscraper · 01-19-2023, 09:11 AM

^^^Correct.
You need to have a CAT or the PCM needs to be reprogramed to not read the second O2. If the JB4 does not have the option to turn off the second O2 then the PCM sees the CAT is not working or missing.
I have no idea if anyone does custom tunes on this generation.

And I know the PCM is called something different now. I just can't think of it... I'm Old!

nazzri · 01-19-2023, 04:18 PM

So apparently I’m Australia it can be removed with JB4

The code I’m getting is

129002 Lambda probe before catalytic converter, signal lines, short circuit to ground.

LongBeachDinanFan · 01-19-2023, 04:28 PM

That isn't a code from downpipes it's a problem with one of your oxygen sensors wiring.

nazzri · 01-19-2023, 04:43 PM

Quote:

Originally Posted by LongBeachDinanFan

That isn't a code from downpipes it's a problem with one of your oxygen sensors wiring.

Any idea on what I need to change to clear it?

LongBeachDinanFan · 01-19-2023, 05:29 PM

I imagine you have to go fix what is wrong with the sensor.

Hit_Apex · 01-19-2023, 05:44 PM

Quote:

Originally Posted by nazzri

Any idea on what I need to change to clear it?

Sounds like the O2 harnesses are mixed up, not plugged in correctly. Take it to someone who knows how to fix it or do the research and diagnose yourself. Better yet, have the DP installer correct their mistake.

Info@mad-us.com · 01-20-2023, 02:00 PM

Quote:

Originally Posted by Hit_Apex

Sounds like the O2 harnesses are mixed up, not plugged in correctly. Take it to someone who knows how to fix it or do the research and diagnose yourself. Better yet, have the DP installer correct their mistake.

This. It's a top primary sensor either its not connected properly/broken. If it was backwards it would be driving pretty bad.

A cel from catless downpipe would be a code from the secondary bottom sensors. Catalytic efficiency

Warlawd · 01-20-2023, 03:26 PM

I am looking to do catless DP on my car and ran into this

https://www.armmotorsports.com/produ...-kit-n63-n63tu

Hit_Apex · 01-20-2023, 05:15 PM

Quote:

Originally Posted by Warlawd

I am looking to do catless DP on my car and ran into this

https://www.armmotorsports.com/produ...-kit-n63-n63tu

An alternative to BDG mini-cat (possibly). No indication if these have elements inside and would like detail on how this is accomplished: spacers specifically calibrated to comply with BMW's parameters for a functioning catalyst

Hendo741 · 01-20-2023, 05:29 PM

JB4 cant disable the code, only clear it temporarily. You'd have to get a flash tune to disable it.

nazzri · 01-20-2023, 05:33 PM

That’s what I thought but apparently in AUS it can

Info@mad-us.com · 01-20-2023, 10:46 PM

Quote:

Originally Posted by nazzri

That’s what I thought but apparently in AUS it can

Yeah pretty sure that's a USA thing only.

01-19-2023, 06:54 AM	#1
nazzri New Member 2 Rep 9 Posts Drives: bmw 320i e90 Join Date: Aug 2013 Location: nsw australia iTrader: (0)	catless downpipe throwing cel even with jb4? Featured on BIMMERPOST.com Hey guys had the engine light for a while, got told if I get jb4 it’ll get rid of it. I have the jb4 and the engine light came back the next day. Is there anything I can do to stop it from coming on?
	Appreciate 1 juniM31.50 Tweet Quote

01-19-2023, 09:05 AM	#2
mike@x-ph.com BimmerPost Supporting Vendor 24083 Rep 190,614 Posts Drives: 07-335/12-328/18-M4/21-M4CP Join Date: Sep 2013 Location: Las Vegas iTrader: (23)	What you were told was, unfortunately, not accurate. The JB4 does not hide the check engine light. I recommend you invest in a downpipe that does not trigger the check engine light; Active Autowerks catted is the best. __________________ Check out our current sale by clicking on this link! https://x-ph.com/sale/ Phone number 702-494-9435
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01-19-2023, 09:11 AM	#3
Skyscraper Captain 2184 Rep 687 Posts Drives: 2023 BMW M4 Competition Join Date: Dec 2022 Location: Rocklin, CA iTrader: (0) Garage List 2023 BMW M4 Competi ... [9.22] 2007 Porsche GT3RS [10.00]	^^^Correct. You need to have a CAT or the PCM needs to be reprogramed to not read the second O2. If the JB4 does not have the option to turn off the second O2 then the PCM sees the CAT is not working or missing. I have no idea if anyone does custom tunes on this generation. And I know the PCM is called something different now. I just can't think of it... I'm Old!
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01-19-2023, 04:18 PM	#4
nazzri New Member 2 Rep 9 Posts Drives: bmw 320i e90 Join Date: Aug 2013 Location: nsw australia iTrader: (0)	So apparently I’m Australia it can be removed with JB4 The code I’m getting is 129002 Lambda probe before catalytic converter, signal lines, short circuit to ground.
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01-19-2023, 04:28 PM	#5
LongBeachDinanFan Lieutenant 285 Rep 503 Posts Drives: M3 Join Date: Jan 2015 Location: LB, CA iTrader: (0)	That isn't a code from downpipes it's a problem with one of your oxygen sensors wiring.
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01-19-2023, 05:29 PM	#7
LongBeachDinanFan Lieutenant 285 Rep 503 Posts Drives: M3 Join Date: Jan 2015 Location: LB, CA iTrader: (0)	I imagine you have to go fix what is wrong with the sensor.
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01-20-2023, 03:26 PM	#10
Warlawd Lt 31 Rep 58 Posts Drives: G80 M3 Join Date: Jan 2015 Location: United States iTrader: (0)	Arm cel delete kit I am looking to do catless DP on my car and ran into this https://www.armmotorsports.com/produ...-kit-n63-n63tu
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01-20-2023, 05:29 PM	#12
Hendo741 Chief Petty Officer 645 Rep 517 Posts Drives: 22 M4CX / 22 X3MC Join Date: Dec 2021 Location: US iTrader: (0)	JB4 cant disable the code, only clear it temporarily. You'd have to get a flash tune to disable it. __________________
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01-20-2023, 05:33 PM	#13
nazzri New Member 2 Rep 9 Posts Drives: bmw 320i e90 Join Date: Aug 2013 Location: nsw australia iTrader: (0)	That’s what I thought but apparently in AUS it can
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