Misfire & HPFP

S.yen · 06-09-2015, 11:21 AM

Had a misfire on cylinder 2 a few days ago, and wondering if the HPFP is working properly?
(currently running with cobbAP stage1 91map)
Here's my datalog
http://datazap.me/u/syen827/log-1433...2&data=1-11-13

enrita · 06-09-2015, 01:27 PM

if the hpfp has issues you will get a related code. check the missfire thread for solutions and troubleshooting

335NJ · 06-09-2015, 10:51 PM

From N54Tech: FP_H: Fuel pressure, high system. Otherwise known as the high pressure pump. Note all N54 include this and N55 can only log this if also equipped with the flex fuel connector. This value represents the voltage of the high pressure 0-5V sensor, where a value of 20 is 5v. Each unit of measure is roughly equal to 150psi. Typical values at full throttle are 10-14, or 1500 to 2100psi. Values of less than 900psi as full throttle indicate a fuel delivery problem and the JB4 will failsafe at 700psi at full throttle. Note when not at full throttle a typical value is 5 or 750psi.

That's for JB4, I'm on mobile so it's a PITA to interpret logs. I don't remember exactly how COBB shows the HPFP, but the psi values above are accurate regardless.

TBL_335i · 06-10-2015, 12:27 AM

When my car was misfiring I replaced the ignition coils and spark plugs.

mike@x-ph.com · 06-10-2015, 01:07 PM

You need to post a dalatalog for a pull ( 2500rpm to 6000 with pedal being 100%) so we can see how your HPFP is performing under pressure.

Mike@N54Tuning.com · 06-11-2015, 08:32 AM

First question is always how old are the spark plugs. 90% of misfires can usually be solved by new plugs. Start there, especially if they haven't been changed in a while. It seems most on this platform overlook changing their plugs which should be changed every 15-20K when tuned.

Mike

06-09-2015, 11:21 AM	#1
S.yen Private First Class 15 Rep 126 Posts Drives: E92 335i Join Date: Feb 2008 Location: Vancouver iTrader: (0) Garage List 07' E92 335 [0.00]	Misfire & HPFP Had a misfire on cylinder 2 a few days ago, and wondering if the HPFP is working properly? (currently running with cobbAP stage1 91map) Here's my datalog http://datazap.me/u/syen827/log-1433...2&data=1-11-13 __________________ 07' E92 AW 335 /navi /sport pkg /active steering /Hamann front lip /hamann side skirt /hamann diffuser/ Hamann quad exhaust /AC roof spoiler /oem rear spoiler /CF grill /6000K D1S/ mtec 4750K angel eye & fog light /35% tint /CF mirror / Work Schwert SC2 20" 245front 285rear / Koni FSD & Eibach Pro-Kit
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06-09-2015, 01:27 PM	#2
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	if the hpfp has issues you will get a related code. check the missfire thread for solutions and troubleshooting __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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06-09-2015, 10:51 PM	#3
335NJ Colonel 533 Rep 2,872 Posts Drives: 2008 335i 6MT E90 Join Date: Feb 2014 Location: NJ/Philadelphia Suburbs iTrader: (1)	From N54Tech: FP_H: Fuel pressure, high system. Otherwise known as the high pressure pump. Note all N54 include this and N55 can only log this if also equipped with the flex fuel connector. This value represents the voltage of the high pressure 0-5V sensor, where a value of 20 is 5v. Each unit of measure is roughly equal to 150psi. Typical values at full throttle are 10-14, or 1500 to 2100psi. Values of less than 900psi as full throttle indicate a fuel delivery problem and the JB4 will failsafe at 700psi at full throttle. Note when not at full throttle a typical value is 5 or 750psi. That's for JB4, I'm on mobile so it's a PITA to interpret logs. I don't remember exactly how COBB shows the HPFP, but the psi values above are accurate regardless.
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06-10-2015, 12:27 AM	#4
TBL_335i Enlisted Member 9 Rep 38 Posts Drives: 2007 space grey 335i Join Date: Jun 2015 Location: Fremont iTrader: (0)	When my car was misfiring I replaced the ignition coils and spark plugs.
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06-10-2015, 01:07 PM	#5
mike@x-ph.com BimmerPost Supporting Vendor 24501 Rep 191,503 Posts Drives: 07-335/12-328/18-M4/21-M4CP Join Date: Sep 2013 Location: Las Vegas iTrader: (23)	You need to post a dalatalog for a pull ( 2500rpm to 6000 with pedal being 100%) so we can see how your HPFP is performing under pressure. __________________ Check out our current sale by clicking on this link! https://x-ph.com/sale/ Phone number 702-494-9435
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06-11-2015, 08:32 AM	#6
Mike@N54Tuning.com Joint Chiefs of Staff 4927 Rep 116,037 Posts Drives: 2007 335i, 2015 M3 Join Date: Dec 2008 Location: N54tuning.com iTrader: (89)	First question is always how old are the spark plugs. 90% of misfires can usually be solved by new plugs. Start there, especially if they haven't been changed in a while. It seems most on this platform overlook changing their plugs which should be changed every 15-20K when tuned. Mike
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