Fuel pressure

Elmo370z · 05-15-2017, 03:43 PM

The car isn't holding fuel pressure it's now sitting around 46 psi driving around in the hot fl heat. It doesn't have any fuel system upgrades besides the rrp. I scheduled to get a tune tomorrow but thinking about cancelling because of the fuel pressure drop. Any info would be appreciated

Jayhovah · 05-15-2017, 03:51 PM

Rrp?

Hotrodz · 05-15-2017, 04:21 PM

Quote:

Originally Posted by Jayhovah

Rrp?

CJM road race pump!

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Elmo370z · 05-15-2017, 06:14 PM

Yes

Elmo370z · 05-15-2017, 06:21 PM

Would the tune be even worth it if it's not holding pressure

Hotrodz · 05-15-2017, 06:48 PM

It depends on when the fuel pressure falls off. If it happens fairly quickly then no you need to find a fix first. If you can get some throttle into it then at that point boost can be cut. This is why the fuel return systems were developed. You want to keep boost in a range that you don't loose fuel pressure or it will go boom!

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Elmo370z · 05-15-2017, 06:59 PM

Gotcha. Guess I'll keep an eye on it when it's on the dyno. I replaced the pump and went to an external jet to fix the old issue. Maybe the stock fuel fuel pump could be bad

Hotrodz · 05-15-2017, 07:05 PM

Quote:

Originally Posted by Elmo370z

Gotcha. Guess I'll keep an eye on it when it's on the dyno. I replaced the pump and went to an external jet to fix the old issue. Maybe the stock fuel fuel pump could be bad

Yeah I would check it out and make sure there are no issues with voltage or the top hat or could just be bad!

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Elmo370z · 05-15-2017, 07:07 PM

That's the code, voltage issue

phunk · 05-15-2017, 07:13 PM

I wouldnt get the car tuned if the fuel pressure isnt correct... because the fuel pressure has a big effect on the tune during full throttle when the ECU goes outside of closed loop feedback.

Elmo370z · 05-15-2017, 07:34 PM

Quote:

Originally Posted by phunk

I wouldnt get the car tuned if the fuel pressure isnt correct... because the fuel pressure has a big effect on the tune during full throttle when the ECU goes outside of closed loop feedback.

That's what I figured. Going to wake up first thing in the morning and look at the sending unit. Got damn z day prep

05-15-2017, 03:43 PM	#1 (permalink)
Elmo370z A True Z Fanatic Join Date: Apr 2013 Location: st. petersburg Posts: 5,707 Drives: 09 nissan 370z Sp M6 Rep Power: 295378	Fuel pressure The car isn't holding fuel pressure it's now sitting around 46 psi driving around in the hot fl heat. It doesn't have any fuel system upgrades besides the rrp. I scheduled to get a tune tomorrow but thinking about cancelling because of the fuel pressure drop. Any info would be appreciated

05-15-2017, 06:48 PM	#6 (permalink)
Hotrodz Premium Member Join Date: Aug 2012 Location: NW, AZ Posts: 9,330 Drives: 10 Nissan 370z Nismo Rep Power: 2684384	It depends on when the fuel pressure falls off. If it happens fairly quickly then no you need to find a fix first. If you can get some throttle into it then at that point boost can be cut. This is why the fuel return systems were developed. You want to keep boost in a range that you don't loose fuel pressure or it will go boom! Sent from my SM-N910P using Tapatalk __________________ *Fast Intentions TT Installed and Tuned by Seb at SpecialtyZ 610whp 560tq:\|Fast Intentions 3" TT-TDX*\|SpecialtyZ/Fast Intentions 72 Row Oil Cooler\|SZ 6 Puck Clutch & Flywheel\|3GsCustoms\|Z1\|Wavetrac\|Hotchkis\|Whiteline \|Blitz\|Fortune Auto 500\|Fujimura\|SPL\|H&R\|TK\|TWM\|RPM Rollbar\|Sparco\|Next Level Performance\|TrackSpec\|AeroFlow Dynamics\|Pioneer\|

05-15-2017, 07:07 PM	#9 (permalink)
Elmo370z A True Z Fanatic Join Date: Apr 2013 Location: st. petersburg Posts: 5,707 Drives: 09 nissan 370z Sp M6 Rep Power: 295378	That's the code, voltage issue Hotrodz likes this.

05-15-2017, 07:13 PM	#10 (permalink)
phunk A True Z Fanatic Join Date: Mar 2009 Location: Chicago Posts: 3,655 Drives: 370 Rep Power: 944523	I wouldnt get the car tuned if the fuel pressure isnt correct... because the fuel pressure has a big effect on the tune during full throttle when the ECU goes outside of closed loop feedback. Hotrodz likes this. __________________ Charles @ CJ Motorsports : Website \| Facebook \| Instagram \| YouTube Home of the 9 second, stock longblock, stock drivetrain 6MT 370z. 9.91 @ 142mph

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05-15-2017, 06:14 PM	#4 (permalink)
Elmo370z A True Z Fanatic Join Date: Apr 2013 Location: st. petersburg Posts: 5,707 Drives: 09 nissan 370z Sp M6 Rep Power: 295378	Yes

05-15-2017, 06:21 PM	#5 (permalink)
Elmo370z A True Z Fanatic Join Date: Apr 2013 Location: st. petersburg Posts: 5,707 Drives: 09 nissan 370z Sp M6 Rep Power: 295378	Would the tune be even worth it if it's not holding pressure

05-15-2017, 06:59 PM	#7 (permalink)
Elmo370z A True Z Fanatic Join Date: Apr 2013 Location: st. petersburg Posts: 5,707 Drives: 09 nissan 370z Sp M6 Rep Power: 295378	Gotcha. Guess I'll keep an eye on it when it's on the dyno. I replaced the pump and went to an external jet to fix the old issue. Maybe the stock fuel fuel pump could be bad