Idling Issues Causes by HFC

C|3R1C · 10-19-2011, 11:56 PM

Hi, I am relatively new to the forum (other than searching through it) so I hope this topic is the in right place.

I was wondering if anyone has encountered a problem using high flow cats? I currently drive an E93 M3 (2010) and I have AA cat back and had AA HFC. When I mean had, I just swapped them out today with my old OEM ones because every time I turn on the car, the idle gets super rough and kicks on the "Engine Malfunction". Took it to the dealer before I took the HFC off and they complained my problem is from the HFC so they just cleared the error codes, but that did not help. So I turned it back to stock and they cleared the codes again (only) since the cat back was apparently hindering warranty again and could be the causing of my problem. Now with the OEM cats on, the car idles super rough when it is turned on, but not enough to cause engine malfunction. I had the HFC for over 12k miles and the cat back for over 20k, and the second I took it in for new brakes last Thursday and got my car back, this problem started happening. Anyone with similar experience or knowledge about why this would happen?

1sikbmr · 10-20-2011, 12:40 AM

HFC will not cause rough idle. Dealer is bullshitting you.

C|3R1C · 10-20-2011, 01:05 AM

That's what I said too, but they won't let up unless I guaranty them I will pay if it is my fault... I also heard a rumor that the problem could be a faulty idling valve?

BPMSport · 10-20-2011, 01:13 AM

Sounds like you have a sensor that is malfunctioning.

I'd check the o2 sensors and make sure the voltage is in spec and that they are cycling properly.

1MOREMOD · 10-20-2011, 01:14 AM

was the engine malfuntion an increased emissions warning or something else?

C|3R1C · 10-20-2011, 01:22 AM

As far as I know, my mechanic friend and I put the four sensors in the right way and I no longer have "Increased Emissions" warning on. Think this would have any relation whatsoever to the cat back? I put the OEM cats and x-pipe back on so as far as the dealer is concerned, the only mod is the cat back.

C|3R1C · 10-20-2011, 01:25 AM

Oh Chris sorry did not see your post till after the reply to Mike. The engine malfunction wasn't related to the increased emissions from what I can tell because that SES light was on (when I had the HFC) for the entire life of the HFC (12k miles) with no problems at all. This engine malf. comes from a super rough, couging idle right when I turn on the car. I found a way to bypass it by putting it into gear and throttling up to quickly take it out of idle state and that kept the engine malf. warning off, but then the car would run more rough than usual.

C|3R1C · 10-20-2011, 01:25 AM

IDK if this helps but my car is also DCT.

akh23456 · 10-20-2011, 06:53 AM

has to be bad 02 sensors i believe.

bigjae1976 · 10-20-2011, 07:43 AM

+1...should be the front sensors. Maybe you switched them???

I believe the rear sensors are for emissions purposes...shouldn't affect the idle.

1MOREMOD · 10-20-2011, 09:47 AM

I don't think they can be switched as the fronts aren't long enough to reach the rear position unless removed from the car then reintstalled which most people don't do as the are a PIA to remove from the engine end.

THE TECH · 10-20-2011, 09:54 AM

Did you have any programming done for the x-pipe? Could the dealer have updated your programming and thus erased any aftermarket programming you had in place?

bigjae1976 · 10-20-2011, 10:25 AM

Quote:

Originally Posted by chriszeh

I don't think they can be switched as the fronts aren't long enough to reach the rear position unless removed from the car then reintstalled which most people don't do as the are a PIA to remove from the engine end.

I mean putting the front bank 1 sensor into bank 2 and vice versa...but I believe that would also cause the car to run crappy all of the time.

1MOREMOD · 10-20-2011, 10:36 AM

probably so.

C|3R1C · 10-20-2011, 11:12 AM

No software at all, at least, not yet. Only mods were the x-pipe and cat back. I let the DME sort itself out. As for the sensors, they were put on right because the first time I installed the x-pipe everything was great. Not one problem. Car ran perfect and smooth. It was right after I got it back from the dealer the engine started messing up. When I turned on the car, it would go through it normal cat heat cycle (but not smoothly), then the revs would start jumping up then engine malf.

1sikbmr · 10-20-2011, 11:41 AM

Dealer fucked it up

Grail05 · 10-20-2011, 11:43 AM

Quote:

Originally Posted by 1sikbmr

Dealer fucked it up

YEAP THEY WENT HAPPY with your car when test driving it...

BTW WHAT DEALER IS THIS...

C|3R1C · 10-20-2011, 05:54 PM

So I asked a BMW tech my friend knows about the O2 sensors, and he said if there is a leak, there would be a problem and the car would go nuts if it started detecting large amounts of O2. Going through the pipes again to make sure, but I'm starting to think that it might be a problem because they cannot find anything else that is wrong. The dealership I go to is actually a great place, especially my SA. Techs just hate being liable for stuff. Gonna redo installing the HFC again on monday and see whats up.

Malek@MRF · 10-20-2011, 05:57 PM

Quote:

Originally Posted by bigjae1976

I mean putting the front bank 1 sensor into bank 2 and vice versa...but I believe that would also cause the car to run crappy all of the time.

This would be pretty much impossible as the harness is not long enough to do this.

BPMSport · 10-21-2011, 03:43 AM

Quote:

Originally Posted by C|3R1C

So I asked a BMW tech my friend knows about the O2 sensors, and he said if there is a leak, there would be a problem and the car would go nuts if it started detecting large amounts of O2. Going through the pipes again to make sure, but I'm starting to think that it might be a problem because they cannot find anything else that is wrong. The dealership I go to is actually a great place, especially my SA. Techs just hate being liable for stuff. Gonna redo installing the HFC again on monday and see whats up.

It's good measure to check the physical sensors, but the best thing to do is to read the o2 sensor voltages postcat and precat and make sure there isn't any anomoly there. Then you can eliminate the o2's if they are not the cause of this. The post cat o2 sensors wouldn't casue rough running, they would just illuminate the CEL and Incrased Emissions in the iDrive.

Changing the secondary cats or rear sections shouldn't cause the CEL to illuminate as long as the primary cats or sensors were not upset in the process. If there is an issue where the o2 sensor isn't working properly due to some sort of leak, that could cause sporadic issues.

Grail05 · 10-21-2011, 07:57 AM

so what dealer is this again... just asking cause i know your local....

bigjae1976 · 10-21-2011, 09:17 AM

Quote:

Originally Posted by Malekreza11

This would be pretty much impossible as the harness is not long enough to do this.

I was talking about the front sensors. But now that I think about it, this isn't like the E46 where the bungs were close to each other. DOH!

10-19-2011, 11:56 PM	#1
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	Idling Issues Causes by HFC Hi, I am relatively new to the forum (other than searching through it) so I hope this topic is the in right place. I was wondering if anyone has encountered a problem using high flow cats? I currently drive an E93 M3 (2010) and I have AA cat back and had AA HFC. When I mean had, I just swapped them out today with my old OEM ones because every time I turn on the car, the idle gets super rough and kicks on the "Engine Malfunction". Took it to the dealer before I took the HFC off and they complained my problem is from the HFC so they just cleared the error codes, but that did not help. So I turned it back to stock and they cleared the codes again (only) since the cat back was apparently hindering warranty again and could be the causing of my problem. Now with the OEM cats on, the car idles super rough when it is turned on, but not enough to cause engine malfunction. I had the HFC for over 12k miles and the cat back for over 20k, and the second I took it in for new brakes last Thursday and got my car back, this problem started happening. Anyone with similar experience or knowledge about why this would happen?
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10-20-2011, 12:40 AM	#2
1sikbmr Brigadier General 145 Rep 3,329 Posts Drives: F80 M3 6MT Join Date: Mar 2010 Location: New York iTrader: (16)	HFC will not cause rough idle. Dealer is bullshitting you. __________________ F80 ///M3 6MT Avus Blue ZCP
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10-20-2011, 01:05 AM	#3
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	That's what I said too, but they won't let up unless I guaranty them I will pay if it is my fault... I also heard a rumor that the problem could be a faulty idling valve?
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10-20-2011, 01:13 AM	#4
BPMSport BimmerPost Supporting Vendor 3388 Rep 7,542 Posts Drives: Harrop M3 / F10 M5 / F82 M4 Join Date: Apr 2008 Location: SoCal iTrader: (9) Garage List 2000 BMW M5 [0.00] 1990 BMW 735i Turbo [0.00] 2008 BMW M3 [7.50] 2015 BMW M3 [0.00] 2015 BMW M5 [0.00]	Sounds like you have a sensor that is malfunctioning. I'd check the o2 sensors and make sure the voltage is in spec and that they are cycling properly. __________________ -----\| Like us on Facebook \| Instagram \|\| Tuning Information \| Remote Coding \|----- ----Visit us at www.BPMSport.com - Emotion. Driven. \| Toll Free: (888) 557-5133----
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10-20-2011, 01:14 AM	#5
1MOREMOD - 11818 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	was the engine malfuntion an increased emissions warning or something else? __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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10-20-2011, 01:22 AM	#6
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	As far as I know, my mechanic friend and I put the four sensors in the right way and I no longer have "Increased Emissions" warning on. Think this would have any relation whatsoever to the cat back? I put the OEM cats and x-pipe back on so as far as the dealer is concerned, the only mod is the cat back.
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10-20-2011, 01:25 AM	#7
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	Oh Chris sorry did not see your post till after the reply to Mike. The engine malfunction wasn't related to the increased emissions from what I can tell because that SES light was on (when I had the HFC) for the entire life of the HFC (12k miles) with no problems at all. This engine malf. comes from a super rough, couging idle right when I turn on the car. I found a way to bypass it by putting it into gear and throttling up to quickly take it out of idle state and that kept the engine malf. warning off, but then the car would run more rough than usual.
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10-20-2011, 06:53 AM	#9
akh23456 All I do is Win... Eat Race Sleep 153 Rep 2,184 Posts Drives: 2018 Range 2011 M3 2019 600lt Join Date: Mar 2009 Location: South Jersey iTrader: (2) Garage List 2019 McLaren 600 LT [0.00] 2011 e90 M3 [0.00] 2018 Range Rover Au ... [0.00]	has to be bad 02 sensors i believe. __________________ Rs7 : 10.4 133.50 with a 1.7 60ft Toyo R888 F10 M5: 11.308 131.96 with a 1.9 60ft Street Tires E90 M3: 11.2 126.7 with a 1.8 60ft Street Tires
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10-20-2011, 07:43 AM	#10
bigjae1976 Major General 1579 Rep 8,077 Posts Drives: 11 E90 M3 Individual Join Date: Mar 2006 Location: Houston, TX iTrader: (22) Garage List 2004 BMW M3 [4.50] 2011 BMW E90 M3 [5.25] 2013 BMW 328i [5.00]	+1...should be the front sensors. Maybe you switched them??? I believe the rear sensors are for emissions purposes...shouldn't affect the idle. __________________ 2018 F30 320iX Melbourne Red 2011 E90 M3 Monte Carlo Blue 2004 E46 M3 Imola Red 2000 E36/7 Z3 Steel Blue
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10-20-2011, 09:47 AM	#11
1MOREMOD - 11818 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	I don't think they can be switched as the fronts aren't long enough to reach the rear position unless removed from the car then reintstalled which most people don't do as the are a PIA to remove from the engine end. __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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10-20-2011, 09:54 AM	#12
THE TECH BimmerPost Supporting Vendor 307 Rep 13,093 Posts Drives: BPMsport 2012 E92 M3 Join Date: Jun 2011 Location: Kansas iTrader: (45) Garage List 2013 Nissan GTR [0.00] 2019 Sierra Denali ... [0.00] 1999 Nissan Silvia [0.00] 1999 Nissan Skyline ... [0.00] 1998 Toyota Supra [0.00]	Did you have any programming done for the x-pipe? Could the dealer have updated your programming and thus erased any aftermarket programming you had in place?
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10-20-2011, 10:36 AM	#14
1MOREMOD - 11818 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	probably so. __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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10-20-2011, 11:12 AM	#15
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	No software at all, at least, not yet. Only mods were the x-pipe and cat back. I let the DME sort itself out. As for the sensors, they were put on right because the first time I installed the x-pipe everything was great. Not one problem. Car ran perfect and smooth. It was right after I got it back from the dealer the engine started messing up. When I turned on the car, it would go through it normal cat heat cycle (but not smoothly), then the revs would start jumping up then engine malf.
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10-20-2011, 11:41 AM	#16
1sikbmr Brigadier General 145 Rep 3,329 Posts Drives: F80 M3 6MT Join Date: Mar 2010 Location: New York iTrader: (16)	Dealer fucked it up __________________ F80 ///M3 6MT Avus Blue ZCP
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10-20-2011, 05:54 PM	#18
C\|3R1C So Kewl Guy 49 Rep 619 Posts Drives: 2010 E93 M3 DCT Join Date: Sep 2011 Location: Los Angeles iTrader: (3)	So I asked a BMW tech my friend knows about the O2 sensors, and he said if there is a leak, there would be a problem and the car would go nuts if it started detecting large amounts of O2. Going through the pipes again to make sure, but I'm starting to think that it might be a problem because they cannot find anything else that is wrong. The dealership I go to is actually a great place, especially my SA. Techs just hate being liable for stuff. Gonna redo installing the HFC again on monday and see whats up.
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10-21-2011, 07:57 AM	#21
Grail05 Putcha ang ganda... 281 Rep 5,441 Posts Drives: 17 F82 M4 Join Date: Feb 2010 Location: Los Angeles, Brea CA. iTrader: (10)	so what dealer is this again... just asking cause i know your local.... __________________
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