Can HPFP be Measured Directly?

techforge · 10-28-2008, 04:47 PM

I was talking to a private mechanic today who comes from Volvo land so he's not real familiar with BMW. I mentioned the problem with the HPFP and there doesn't seem to be a way to predict failure other than long cranks or strange limps. He said why not hook up a fuel pressure gauge to the fuel rail and see if it drops under load. He also thought long cranks were indicative because most ecu's require a minimum psi or they won't fire the plugs. I told him I didn't think there was a way to do that on the N54, plus your standard gauge wouldn't work with the high pressure. Does anyone know if it's possible to check fuel pressure?

1clean335i · 10-28-2008, 07:48 PM

fuel pressure can be checked with a gt-1.... there should already be a fault in the car is there is an issue with the hpfp though...

techforge · 10-29-2008, 12:25 PM

So there could be a fault code for the hpfp without tripping the SES light?

10-28-2008, 04:47 PM	#1
techforge Lieutenant 29 Rep 577 Posts Drives: 335xi coupe Join Date: Jul 2008 Location: Denver iTrader: (2)	Can HPFP be Measured Directly? I was talking to a private mechanic today who comes from Volvo land so he's not real familiar with BMW. I mentioned the problem with the HPFP and there doesn't seem to be a way to predict failure other than long cranks or strange limps. He said why not hook up a fuel pressure gauge to the fuel rail and see if it drops under load. He also thought long cranks were indicative because most ecu's require a minimum psi or they won't fire the plugs. I told him I didn't think there was a way to do that on the N54, plus your standard gauge wouldn't work with the high pressure. Does anyone know if it's possible to check fuel pressure?
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10-28-2008, 07:48 PM	#2
1clean335i Perf BMW mag issue 147, 159 435 Rep 6,799 Posts Drives: Project Estoril Join Date: Feb 2007 Location: Miami, FL iTrader: (31) Garage List 2013 335i M-sport [0.00] 2011 X5 xdrive35i M ... [0.00] 2009 335i M-sport [0.00] 07' 335i Sedan [0.00]	fuel pressure can be checked with a gt-1.... there should already be a fault in the car is there is an issue with the hpfp though... __________________ '13 Estoril Blue 335i M-sport *Don't PM me!* Message me here- http://www.facebook.com/ProjectEstoril
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10-29-2008, 12:25 PM	#3
techforge Lieutenant 29 Rep 577 Posts Drives: 335xi coupe Join Date: Jul 2008 Location: Denver iTrader: (2)	So there could be a fault code for the hpfp without tripping the SES light?
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