E85, 29F3, and some serious engine malfunctions.

Sean978 · 11-12-2014, 01:50 PM

So I was recently out on a cruise, some spirited driving involved. Coming through the mountains I experienced a major loss of power, SES light, and a 29F3 code.

While coasting to a stop and pulling into a pulloff to park, I tried to throttle into a parking space, and noticed that the car had literally no power. I'm talking foot to the floor and the car takes a good 3 seconds to rev up to about 2500-3000k RPM, no boost building. Engine has hard shuddering at idle (RPMs will fluctuate from 300-1000) before dropping to around 400-500rpm.

The cruise was a rather large one with 200+ cars, so multiple people stopped to offer their prognosis, with one BMW tech stopping to offer his advice. Told him I was running 40% ethanol to 60% 93, to which he rebutted that even with aftermarket tuning these motors could not handle more than 10% ethanol. He believes the ethanol mixture cooked the HPFP and Injectors. I have been running ethanol at this mixture for about 4 months without issues. I was literally at 120,566 miles at this time and we all know the HPFP is warrantied until 120k.

I've searched and searched and searched and from what I've found most if not all folks getting the 29F3 code can run normally until they go WOT. The car is at the shop right now as i've told them not to do anything with it as far as tear down until I could point them in a certain direction. I have serious doubts that ONLY the lpfp sensor is faulty, the symptoms seem to point to something more serious.

My question is; Has anyone experienced anything remotely similiar?? (for what its worth the BMW tech that stopped to help said he felt the car was only running on 2-3 cylinders at best. It was a 155 mile tow home ... Thank god for AAA.

Mods are jb4 G5, kittyless DPs, DCI. 40% Ethanol. Running map5 at the time and was not near WOT, just coasting downhill.

SteveAZ · 11-12-2014, 02:24 PM

Take a log at idle and post it up so we can see what's going on. A bad LPFP sensor will usually read 87psi and the DME will run the LPFP at 100% duty cycle to compensate.

cn555ic · 11-12-2014, 08:13 PM

Yes change out your low pressure fuel sensor! That the same symptoms I had with my car....Car would run fine but as soon as you floor it...POP and car feels like a 2 cylinder moped! Turn off the ignition and start the car again, the car would run fine and normal but as soon as you press the throttle 3/4 boom same thing again..

The sensor is about 90 bucks or so but getting to it is quite a task...YOu need to remove air intake, cowl, chargepipe and raise the intake manifold a drop to get to that low pressure sensor sitting right underneath the manifold...

V8bait · 11-12-2014, 08:18 PM

Some BMW techs are little more than parts installers. He was full of it. That's all I have to say about that. As for your issue could be a bunch of things none of which are directly related to the e85.

BMW master techs used to blame the 10% ethanol in our pump gas for the massive amounts of hpfp failures but that was always just a rumor with no evidence.

Welterweight · 11-13-2014, 09:59 AM

Is the use of Ethanol to blame for this guys?!?!

Jklad · 11-13-2014, 12:00 PM

Quote:

Originally Posted by cn555ic

Yes change out your low pressure fuel sensor! That the same symptoms I had with my car....Car would run fine but as soon as you floor it...POP and car feels like a 2 cylinder moped! Turn off the ignition and start the car again, the car would run fine and normal but as soon as you press the throttle 3/4 boom same thing again..

The sensor is about 90 bucks or so but getting to it is quite a task...YOu need to remove air intake, cowl, chargepipe and raise the intake manifold a drop to get to that low pressure sensor sitting right underneath the manifold...

If your just replacing the low pressure sensor, no need to detach intake mani. Just detach charge pipe at tb and push aside, detach 4 throttle body bolts and push aside, slide out the dreaded junction box, and use a really long open wrench to loosen the sensor.

Sean978 · 11-13-2014, 12:46 PM

Update: Went to talk with my mechanic today. He wasn't able to produce any 29F3 codes ... Said he was having hard misfires in 4, 5, 6. First bank is not running lean whatsoever according to him.

Suggested to him we replace the LP sensor, and upgrade the LPFP itself. I plan on getting a backend flash (not decided on the best one yet) that supports higher levels of ethanol.

What's everyones preferred backend flash? Wedge? BB? BMS?

cn555ic · 11-13-2014, 01:04 PM

Quote:

Originally Posted by Jklad

If your just replacing the low pressure sensor, no need to detach intake mani. Just detach charge pipe at tb and push aside, detach 4 throttle body bolts and push aside, slide out the dreaded junction box, and use a really long open wrench to loosen the sensor.

The issue is the junction box is not easy to even slide off. I didnt even need to slide it off...Taking off the bolts off the manifold I was able to raise the manifold up enough to reach the sensor. I didnt have to remove the manifold out of its place....Many will agree that junction box is a royal bitch to slide off..

UMich_335i · 11-13-2014, 01:17 PM

I pulled the junction box off because I was terrified of removing the manifold. I used a metal pick to slide under the latches to "break them loose" from all of the engine bay gunk that had built up.

Also, be sure to use SteveAZ for your lpfp upgrade!!

Jklad · 11-13-2014, 02:04 PM

Quote:

Originally Posted by UMich_335i

I pulled the junction box off because I was terrified of removing the manifold. I used a metal pick to slide under the latches to "break them loose" from all of the engine bay gunk that had built up.

Also, be sure to use SteveAZ for your lpfp upgrade!!

Haha the intake is really not that bad, it's just more bs to have to remove and reinstall!! I was luckily able to slide my box off pretty easily with some wd 40 and a pry tool

Sean978 · 11-19-2014, 04:17 PM

Here is a link to some logs as I was finally able to sneak in and get the USB wire hooked up to the JB4 for logging.

Turns out you can't attach ***.csv files on this forum ...

http://www.n54tech.com/forums/showthread.php?t=27843

Morning Would · 11-21-2014, 01:18 PM

Tagged for how this is resolved. Same issues here. I get the 29F3 all the time. When I really run it hard it throws the SES and sometimes gives me a cylinder 4 misfire also. Simply hit the steering wheel controls and clear the codes. All is well again until I hammer down. Ran 3 gallons E85 and balance 91 every other tank full most of the spring and summer. Since this problem started in late September, I have ran just 91 and do not get on it anymore. I have an appointment to do the Oil filter housing gasket, low pressure fuel sensor and walnut blasting in a couple weeks. Would sure like to know how you resolve this before I go.

11-12-2014, 01:50 PM	#1
Sean978 Private First Class 35 Rep 120 Posts Drives: 2007 335i 6MT SGM Join Date: Jan 2014 Location: Nashua, NH iTrader: (0)	E85, 29F3, and some serious engine malfunctions. So I was recently out on a cruise, some spirited driving involved. Coming through the mountains I experienced a major loss of power, SES light, and a 29F3 code. While coasting to a stop and pulling into a pulloff to park, I tried to throttle into a parking space, and noticed that the car had literally no power. I'm talking foot to the floor and the car takes a good 3 seconds to rev up to about 2500-3000k RPM, no boost building. Engine has hard shuddering at idle (RPMs will fluctuate from 300-1000) before dropping to around 400-500rpm. The cruise was a rather large one with 200+ cars, so multiple people stopped to offer their prognosis, with one BMW tech stopping to offer his advice. Told him I was running 40% ethanol to 60% 93, to which he rebutted that even with aftermarket tuning these motors could not handle more than 10% ethanol. He believes the ethanol mixture cooked the HPFP and Injectors. I have been running ethanol at this mixture for about 4 months without issues. I was literally at 120,566 miles at this time and we all know the HPFP is warrantied until 120k. I've searched and searched and searched and from what I've found most if not all folks getting the 29F3 code can run normally until they go WOT. The car is at the shop right now as i've told them not to do anything with it as far as tear down until I could point them in a certain direction. I have serious doubts that ONLY the lpfp sensor is faulty, the symptoms seem to point to something more serious. My question is; Has anyone experienced anything remotely similiar?? (for what its worth the BMW tech that stopped to help said he felt the car was only running on 2-3 cylinders at best. It was a 155 mile tow home ... Thank god for AAA. Mods are jb4 G5, kittyless DPs, DCI. 40% Ethanol. Running map5 at the time and was not near WOT, just coasting downhill.
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11-12-2014, 02:24 PM	#2
SteveAZ Captain 60 Rep 654 Posts Drives: 135i Cab Join Date: Jul 2012 Location: Phoenix, AZ iTrader: (5)	Take a log at idle and post it up so we can see what's going on. A bad LPFP sensor will usually read 87psi and the DME will run the LPFP at 100% duty cycle to compensate. __________________ 2008 E88--Fuel-It! Stage 4 LPFP & PI--PS2 turbos--JB4/MHD--FBO--662whp/604wtq 2011 E90--Fuel-It! S2BL LPFP and PI--PS2 Turbo--JB4/MHD--FBO--546whp/589wtq 2013 Mini JCW--Tune--DP--FMIC--a couple Fuel-It! goodies--265whp/320wtq 2013 F10--JB4/BM3 2015 F82--Fuel-It! Stage 3 LPFP & PI--PS2 Turbos-- JB4/BM3-FBO
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11-12-2014, 08:13 PM	#3
cn555ic 441 Rep 18,331 Posts Drives: 335i Join Date: Jun 2007 Location: US iTrader: (6)	Yes change out your low pressure fuel sensor! That the same symptoms I had with my car....Car would run fine but as soon as you floor it...POP and car feels like a 2 cylinder moped! Turn off the ignition and start the car again, the car would run fine and normal but as soon as you press the throttle 3/4 boom same thing again.. The sensor is about 90 bucks or so but getting to it is quite a task...YOu need to remove air intake, cowl, chargepipe and raise the intake manifold a drop to get to that low pressure sensor sitting right underneath the manifold... Last edited by cn555ic; 11-12-2014 at 08:19 PM..
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11-12-2014, 08:18 PM	#4
V8bait Lieutenant 406 Rep 574 Posts Drives: e92 335i 6mt Join Date: Oct 2011 Location: Houston iTrader: (1)	Some BMW techs are little more than parts installers. He was full of it. That's all I have to say about that. As for your issue could be a bunch of things none of which are directly related to the e85. BMW master techs used to blame the 10% ethanol in our pump gas for the massive amounts of hpfp failures but that was always just a rumor with no evidence.
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11-13-2014, 09:59 AM	#5
Welterweight Major 98 Rep 1,321 Posts Drives: Truck in snow, coupe in summer Join Date: Jan 2013 Location: Boston iTrader: (3) Garage List 2012 BMW 328i [0.00] 2005 Dodge Ram Quad ... [0.00] 2009 BMW 335xi E92 [10.00]	Is the use of Ethanol to blame for this guys?!?! __________________ 2009 BSM E92 335xi - RR600's/FBO-VRSF/Apex Arc 8/Wedge E60 MHD/Fuel it Stage 2/BMW PE w/ Dimisa Tips/Alpina TCU/Dinan Springs/RB Inlets/3.5 Bar TMAP
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11-13-2014, 12:46 PM	#7
Sean978 Private First Class 35 Rep 120 Posts Drives: 2007 335i 6MT SGM Join Date: Jan 2014 Location: Nashua, NH iTrader: (0)	Update: Went to talk with my mechanic today. He wasn't able to produce any 29F3 codes ... Said he was having hard misfires in 4, 5, 6. First bank is not running lean whatsoever according to him. Suggested to him we replace the LP sensor, and upgrade the LPFP itself. I plan on getting a backend flash (not decided on the best one yet) that supports higher levels of ethanol. What's everyones preferred backend flash? Wedge? BB? BMS?
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11-13-2014, 01:17 PM	#9
UMich_335i Lieutenant 25 Rep 414 Posts Drives: 2009 e90 335i Join Date: Aug 2013 Location: Atlanta, GA iTrader: (0) Garage List 2009 BMW 335i [0.00]	I pulled the junction box off because I was terrified of removing the manifold. I used a metal pick to slide under the latches to "break them loose" from all of the engine bay gunk that had built up. Also, be sure to use SteveAZ for your lpfp upgrade!! __________________ 2009 e90 335i \| AT \| AG M590 \| Conti DW \| KW V1 \| Lux \| Akebono e50 PTF Protune \| Cobb FMIC \| aFe DCI \| VRSF DPs \| ER CP \| Tial BOV \| Alpina Flash \| Fuel-It Stg1 \| RB PCV \| Cobb Exhaust
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11-19-2014, 04:17 PM	#11
Sean978 Private First Class 35 Rep 120 Posts Drives: 2007 335i 6MT SGM Join Date: Jan 2014 Location: Nashua, NH iTrader: (0)	Here is a link to some logs as I was finally able to sneak in and get the USB wire hooked up to the JB4 for logging. Turns out you can't attach ***.csv files on this forum ... http://www.n54tech.com/forums/showthread.php?t=27843
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11-21-2014, 01:18 PM	#12
Morning Would Private 0 Rep 96 Posts Drives: like a boss Join Date: May 2013 Location: just below the poverty line iTrader: (0)	Tagged for how this is resolved. Same issues here. I get the 29F3 all the time. When I really run it hard it throws the SES and sometimes gives me a cylinder 4 misfire also. Simply hit the steering wheel controls and clear the codes. All is well again until I hammer down. Ran 3 gallons E85 and balance 91 every other tank full most of the spring and summer. Since this problem started in late September, I have ran just 91 and do not get on it anymore. I have an appointment to do the Oil filter housing gasket, low pressure fuel sensor and walnut blasting in a couple weeks. Would sure like to know how you resolve this before I go.
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