Fuel Pump Gone? - Focaljet

**IslandFocus** · 10-30-2008, 12:22 PM

As I was driving yesterday, I noticed that my car started running very very lean while cruising.......in the 17s and 18s. I have an electric fuel pressure gauge and it's reading only around 23-25psi at idle and cruise. I generally have my BAP at the 40 mark but even when I turned it up to the 50 max, it still only read about 28psi at best. Is this my fuel pump going bad or........?

**junof** · 10-30-2008, 12:32 PM

Does your gauge read absolute or guage pressure? If it reads absolute the vacuum at cruise would have to be added to your reading to get true fuel pressure. Do you have a boost guage that reads vacuum? Assuming you were running 17-18" of vacuum (about 8.5 psia), your fuel pressure would be 31-33, still a little low. I would check the fuel pressure sensor and filter first.
Do you have a datalogger to check your cycle rate for the pump and injectors?

**IslandFocus** · 10-30-2008, 12:37 PM

Yes, I have the Xcal2 and the gauge is generally around 38-40psi at idle. The fuel filter was changed earlier this year but where is the fuel pressure sensor?

**FocusSportVP** · 10-30-2008, 01:07 PM

Can you disable the BAP for a test?

**IslandFocus** · 10-30-2008, 01:47 PM

I can turn the knob all the way down......would that be the same?

**FocusSportVP** · 10-30-2008, 02:36 PM

No, that doesn't count. I mean it might, but to really know, you need to disconnect. I deal with this kind of thing all the time, trust me on this.

**IslandFocus** · 10-30-2008, 02:40 PM

OK boss, I'll bypass it completely then

**twistyeyes** · 10-30-2008, 02:41 PM

is the fuel pressure sensor on the passanger side of the fuel rail?

**c170zetec** · 10-30-2008, 03:57 PM

yup that's where it is

**polarisman14** · 10-30-2008, 04:37 PM

I thought that was the fuel pulse dampener.

**c170zetec** · 10-30-2008, 07:40 PM

ah f me, you would be correct sir i get my lefts and rights mixed up all the time

**5lick** · 10-30-2008, 08:46 PM

I think the fuel pulse dampener is the big metal thing down the line a bit, and the fuel pressure sensor is the one phisically bolted to the fuel rail on the passenger side.
Mine went out last month. It was leaking all (100%) of my fuel right into the attached vacuum line, straight into the intake mani..

**IslandFocus** · 11-01-2008, 02:39 PM

Ok, I realized today that my fuel pressure gauge DOES measure absolute pressure and the Xcal2 was reading 38-40psi whereas the gauge was reading around 26-28psi. So I put some fuel in the tank and hopefully everything is alright. BTW, I did bypass the BAP but the gauge still read the same so I guess the BAP is fine.

**FocusSportVP** · 11-01-2008, 02:49 PM

Good job.

10-30-2008, 12:22 PM	#1
IslandFocus Senior TEAM Member Join Date: Oct 2004 Location: Nassau, Bahamas Posts: 2,310	Fuel Pump Gone? As I was driving yesterday, I noticed that my car started running very very lean while cruising.......in the 17s and 18s. I have an electric fuel pressure gauge and it's reading only around 23-25psi at idle and cruise. I generally have my BAP at the 40 mark but even when I turned it up to the 50 max, it still only read about 28psi at best. Is this my fuel pump going bad or........? __________________ 2000 Focus ZX3: Xios Turbo Kit on Built Motor in Progress!!

10-30-2008, 12:32 PM	#2
junof Rookie Join Date: Oct 2008 Location: Jupiter Posts: 17	Re: Fuel Pump Gone? Does your gauge read absolute or guage pressure? If it reads absolute the vacuum at cruise would have to be added to your reading to get true fuel pressure. Do you have a boost guage that reads vacuum? Assuming you were running 17-18" of vacuum (about 8.5 psia), your fuel pressure would be 31-33, still a little low. I would check the fuel pressure sensor and filter first. Do you have a datalogger to check your cycle rate for the pump and injectors?

10-30-2008, 12:37 PM	#3
IslandFocus Senior TEAM Member Join Date: Oct 2004 Location: Nassau, Bahamas Posts: 2,310	Re: Fuel Pump Gone? Yes, I have the Xcal2 and the gauge is generally around 38-40psi at idle. The fuel filter was changed earlier this year but where is the fuel pressure sensor? __________________ 2000 Focus ZX3: Xios Turbo Kit on Built Motor in Progress!!

10-30-2008, 01:07 PM	#4
FocusSportVP Premiere Sponsor Join Date: Aug 2000 Location: The Lair of The West Coast Cult Posts: 20,819	Re: Fuel Pump Gone? Can you disable the BAP for a test? __________________ Best Regards, Randy Robles Vice President FocusSport / FSWerks www.focussport.com / www.fswerks.com 714.630.6353 A work in progress - The 384 WHP / 341 WTQ FocusSport Turbo ZX3 - Click me! The FocusSport Street Tuner Challenge Focus 396 WHP / 347 WTQ - Click me!

10-30-2008, 01:47 PM	#5
IslandFocus Senior TEAM Member Join Date: Oct 2004 Location: Nassau, Bahamas Posts: 2,310	Re: Fuel Pump Gone? I can turn the knob all the way down......would that be the same? __________________ 2000 Focus ZX3: Xios Turbo Kit on Built Motor in Progress!!

10-30-2008, 02:36 PM	#6
FocusSportVP Premiere Sponsor Join Date: Aug 2000 Location: The Lair of The West Coast Cult Posts: 20,819	Re: Fuel Pump Gone? No, that doesn't count. I mean it might, but to really know, you need to disconnect. I deal with this kind of thing all the time, trust me on this. __________________ Best Regards, Randy Robles Vice President FocusSport / FSWerks www.focussport.com / www.fswerks.com 714.630.6353 A work in progress - The 384 WHP / 341 WTQ FocusSport Turbo ZX3 - Click me! The FocusSport Street Tuner Challenge Focus 396 WHP / 347 WTQ - Click me!

10-30-2008, 02:40 PM	#7
IslandFocus Senior TEAM Member Join Date: Oct 2004 Location: Nassau, Bahamas Posts: 2,310	Re: Fuel Pump Gone? OK boss, I'll bypass it completely then __________________ 2000 Focus ZX3: Xios Turbo Kit on Built Motor in Progress!!

10-30-2008, 02:41 PM	#8
twistyeyes TEAM Member Join Date: Nov 2006 Location: wichita, ks Posts: 344	Re: Fuel Pump Gone? is the fuel pressure sensor on the passanger side of the fuel rail? __________________ Originally Posted by pitchblack23 I like my chili with kilobeans.

10-30-2008, 03:57 PM	#9
c170zetec Junior Member Join Date: Aug 2007 Location: Edison, NJ Posts: 84	Re: Fuel Pump Gone? yup that's where it is __________________ *Zetec Crew #171* “We are what we repeatedly do. Excellence, then, is not an act but a habit.” — Aristotle, 384-322 B.C.

10-30-2008, 04:37 PM	#10
polarisman14 Senior TEAM Member Join Date: Aug 2006 Location: Henniker, NH Posts: 3,166	Re: Fuel Pump Gone? I thought that was the fuel pulse dampener. __________________ --UnFocused1-- --01 Focus "FCS-PWR" 300+whp Work-In-Progress-- <95 Ranger "SLOWNLO" Project #2: Dropped 4/7, side exit exhaust, audio, etc...> >86 Ninja 250R "GOPED" 50+mpg bullet: Slip-ons, Pod filters, Jet kit, LED signals, custom plate bracket<

10-30-2008, 07:40 PM	#11
c170zetec Junior Member Join Date: Aug 2007 Location: Edison, NJ Posts: 84	Re: Fuel Pump Gone? ah f me, you would be correct sir i get my lefts and rights mixed up all the time __________________ *Zetec Crew #171* “We are what we repeatedly do. Excellence, then, is not an act but a habit.” — Aristotle, 384-322 B.C.

11-01-2008, 02:39 PM	#13
IslandFocus Senior TEAM Member Join Date: Oct 2004 Location: Nassau, Bahamas Posts: 2,310	Re: Fuel Pump Gone? Ok, I realized today that my fuel pressure gauge DOES measure absolute pressure and the Xcal2 was reading 38-40psi whereas the gauge was reading around 26-28psi. So I put some fuel in the tank and hopefully everything is alright. BTW, I did bypass the BAP but the gauge still read the same so I guess the BAP is fine. __________________ 2000 Focus ZX3: Xios Turbo Kit on Built Motor in Progress!!

11-01-2008, 02:49 PM	#14
FocusSportVP Premiere Sponsor Join Date: Aug 2000 Location: The Lair of The West Coast Cult Posts: 20,819	Re: Fuel Pump Gone? Good job. __________________ Best Regards, Randy Robles Vice President FocusSport / FSWerks www.focussport.com / www.fswerks.com 714.630.6353 A work in progress - The 384 WHP / 341 WTQ FocusSport Turbo ZX3 - Click me! The FocusSport Street Tuner Challenge Focus 396 WHP / 347 WTQ - Click me!

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