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What is the max FP_high value

ChrisTSI

Ready to race!
Location
Canada
...on JB4? What value indicates nearing injector or fuel pump capacity ?


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pretty sure duty cycle is injector value , im not 100%, but it should read below 100. and jb4 indicates values their like FP_H and FP_L (Something like that) that reads Fuel pump high and low, but idk what indicates a max value for those.
 

ZuMBLe

Autocross Champion
Location
NY
Car(s)
Alltrack 6MT
pretty sure duty cycle is injector value , im not 100%, but it should read below 100. and jb4 indicates values their like FP_H and FP_L (Something like that) that reads Fuel pump high and low, but idk what indicates a max value for those.
Pretty sure it's actually high pressure fuel pump pressure value. Not sure how it relates to the tune overall though. I know APR IS20 tune cars have low values like 7 to 10 and stock ECU cars have values in the mid teens. You're supposed to multiply that number by another number to get the pressure value. It can be found on the N54 forums.
 

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
The lower the number means it is running out. However, I don't think the jb4 interperates the same for VW as it does for BMW. Like Zumble said above, tuned cars see fp_h values of 7-8 and jb4 only cars see 15-17. My fp_l is in the 80-90s yet I've seen other cars with it as high as 130. The clearest sign that you will be running out of fuel is your trims and the AFR. 50-51 trims is no more fuel. AFR for jb4 only will be around 13:1 plus or minus a little bit. stay under 14. Injectors are the first weak spot on the 1.8 followed by the hpfp.
 

ZuMBLe

Autocross Champion
Location
NY
Car(s)
Alltrack 6MT
The lower the number means it is running out. However, I don't think the jb4 interperates the same for VW as it does for BMW. Like Zumble said above, tuned cars see fp_h values of 7-8 and jb4 only cars see 15-17. My fp_l is in the 80-90s yet I've seen other cars with it as high as 130. The clearest sign that you will be running out of fuel is your trims and the AFR. 50-51 trims is no more fuel. AFR for jb4 only will be around 13:1 plus or minus a little bit. stay under 14. Injectors are the first weak spot on the 1.8 followed by the hpfp.
Doesn't seem like all flashes though. Meltedsolid's FP_H numbers are in the teens. I suppose it's possible he's running a high FOL to force it up. Or the IS20 APR tunes are richer so APR increased the IPW or something resulting in less pressure in the setup. Or something?
 

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
Doesn't seem like all flashes though. Meltedsolid's FP_H numbers are in the teens. I suppose it's possible he's running a high FOL to force it up. Or the IS20 APR tunes are richer so APR increased the IPW or something resulting in less pressure in the setup. Or something?

It could be, but the pump does run at a standard pressure. Too low and there won't be enough for the DI. The standard 1.8 pump is 160 bar and the gti pump is 200 bar
 

ZuMBLe

Autocross Champion
Location
NY
Car(s)
Alltrack 6MT
Here is the description from the JB4 N54 thread. I just checked my IS12 APR Stage 1 logs and see 7s and 8s also for the FP_H. I'd like to know what Melted is running for his FOL. =)

EDIT: Downloaded one of his E30 logs and his FOL is 30 and he's seeing FP_H in the low teens. I have a log of my car on E30ish with FOL 40 and I can't break 10s. My tune is commanding a bit more boost than he's running though.

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FP H:*Fuel pressure, high system. Otherwise known as the high pressure pump. Note all N54 include this and other platforms 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
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TwinDad

Autocross Newbie
Location
Fort Lee, NJ
Here is the description from the JB4 N54 thread. I just checked my IS12 APR Stage 1 logs and see 7s and 8s also for the FP_H. I'd like to know what Melted is running for his FOL. =)

EDIT: Downloaded one of his E30 logs and his FOL is 30 and he's seeing FP_H in the low teens. I have a log of my car on E30ish with FOL 40 and I can't break 10s. My tune is commanding a bit more boost than he's running though.

------------
FP H:*Fuel pressure, high system. Otherwise known as the high pressure pump. Note all N54 include this and other platforms 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
------------

I've seen tons of logs from Ironshade as well. He is is38 APR. Both pass through and stacked he is like yours. The values don't translate the same as they do for the BMW. I believe the BMW JB4 is more involved than ours
 

ZuMBLe

Autocross Champion
Location
NY
Car(s)
Alltrack 6MT
I wonder if there was a change in newer APR tunes and older ones. Melted is the highest FP_H APR tuned car i've seen.


Moot point for me (at least for now), I have a eurodyne cable coming. :D



I've seen tons of logs from Ironshade as well. He is is38 APR. Both pass through and stacked he is like yours. The values don't translate the same as they do for the BMW. I believe the BMW JB4 is more involved than ours
 

MeltedSolid

Autocross Newbie
Location
San Francisco Bay Area
Car(s)
'15 Golf, e36 328i
My tune is still from 2015, so that's possible.
 
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