[satta535i]

i got a new hpfp lpfp o2 sensors and a bpm4 the cars running stronger with the bom4 but my fuel pressure is still dropping

https://www.bootmod3.net/log?id=5fd9...90c60e1369f82f

https://www.bootmod3.net/log?id=5fd9...0b4331d04fa34b

https://www.bootmod3.net/log?id=5fd9...0b4331d04fa348

mod list
ps2 ewg
intake
intercooler
downpipes
walbro 450
bpm4
pr coils
pi installed but not connected yet

[thejeremyman9]

Who did the install of the LPFP and HPFP? Did you have fuel pressure problems before the installs? Were both installed at the same time? Which HPFP?

You're only running about 17psi of boost, and although you have a PS2, realistically you dont need any fuel system upgrades to support this with a stock healthy fuel system. Especially the LPFP. What prompted you to upgrade HPFP and LPFP in the first place?

All signs point to a problem with the HPFP or LPFP. I think the HPFP is harder to 'install wrong' than the LPFP where you could be leaking some supply.

I would also note that, probably due to the HPFP crash, your STFTs are pegged at 1.3 and your AFRs are very unstable and you are going into the mid 14s at full boost, which is not really good, especially on 93. Timing targets are also quite aggressive for a 93 map. I would be weary of doing a lot of pulls like this.

Also, you have a custom tune, so you should be asking your tuner... unless he's the one who told you to upgrade the fuel system in the first place.

I'm looking mostly at this log: https://www.bootmod3.net/log?id=5fd9...0b4331d04fa34b

[satta535i]

Originally Posted by thejeremyman9

Who did the install of the LPFP and HPFP? Did you have fuel pressure problems before the installs? Were both installed at the same time? Which HPFP?

You're only running about 17psi of boost, and although you have a PS2, realistically you dont need any fuel system upgrades to support this with a stock healthy fuel system. Especially the LPFP. What prompted you to upgrade HPFP and LPFP in the first place?

All signs point to a problem with the HPFP or LPFP. I think the HPFP is harder to 'install wrong' than the LPFP where you could be leaking some supply.

I would also note that, probably due to the HPFP crash, your STFTs are pegged at 1.3 and your AFRs are very unstable and you are going into the mid 14s at full boost, which is not really good, especially on 93. Timing targets are also quite aggressive for a 93 map. I would be weary of doing a lot of pulls like this.

Also, you have a custom tune, so you should be asking your tuner... unless he's the one who told you to upgrade the fuel system in the first place.

I'm looking mostly at this log: https://www.bootmod3.net/log?id=5fd9...0b4331d04fa34b

im on a base map were just trying trying to
get the car 100% right now but a shop tested the sending unit and the hpfp and there fine the cars runing better with the bpm4 before the car would cut out at 4500 rpm now it can actually rev out without any fuel cuts

stock hpfp and i always had fuel cuts in the upper rpms since i flashed my ots stage 2 tune but it wouldn't lean out

[thejeremyman9]

Originally Posted by satta535i

im on a base map were just trying trying to
get the car 100% right now but a shop tested the sending unit and the hpfp and there fine the cars runing better with the bpm4 before the car would cut out at 4500 rpm now it can actually rev out without any fuel cuts

stock hpfp and i always had fuel cuts in the upper rpms since i flashed my ots stage 2 tune but it wouldn't lean out

You have a 535, right? Don't they have an extra fuel filter? Something is preventing the fuel flow, because you have WAY more than enough fuel system to support a pump gas tune.

[satta535i]

Originally Posted by thejeremyman9

You have a 535, right? Don't they have an extra fuel filter? Something is preventing the fuel flow, because you have WAY more than enough fuel system to support a pump gas tune.

no i checked only the diesels do we checked the fuel lines there fine too

[thejeremyman9]

Originally Posted by satta535i

no i checked only the diesels do

Which HPFP do you have?

You will need to systematically test, or have a shop test, the fuel system components. Either the LPFP isnt supply enough fuel to the HPFP, or there is an issue with the HPFP.

[satta535i]

Originally Posted by thejeremyman9

Which HPFP do you have?

You will need to systematically test, or have a shop test, the fuel system components. Either the LPFP isnt supply enough fuel to the HPFP, or there is an issue with the HPFP.

i have the stock hpfp we tested the lpfp and the hpfp and the shop concluded it was the ekp so i got the bpm4 could it be the fuel pressure sensor?

[thejeremyman9]

Originally Posted by satta535i

i have the stock hpfp we tested the lpfp and the hpfp and the shop concluded it was the ekp so i got the bpm4 could it be the fuel pressure sensor?

Wait what? I thought you upgraded HPFP? You could just be at the limit of the stock HPFP with your PS2... Although you dont usually need to upgrade it on pump gas, you could be flowing enough air with the PS2 to be running out of fuel. Are you running any extra ethanol?

Why did you upgrade the LPFP and not the HPFP? That's completely backwards, since the HPFP runs out of fueling capacity far before the LPFP.

I don't see how it could be the fuel pressure sensor.

If you switch to a tune with lower boost and the HPFP doesnt crash i would say that's strong evidence its the HPFP itself.

EDIT: I just realized you said you have PI. If you are going PI instead of HPFP for extra fuel, you need to get that turned on and tuned rather than relying on stock HPFP....

[satta535i]

Originally Posted by thejeremyman9

Wait what? I thought you upgraded HPFP? You could just be at the limit of the stock HPFP with your PS2... Although you dont usually need to upgrade it on pump gas, you could be flowing enough air with the PS2 to be running out of fuel. Are you running any extra ethanol?

Why did you upgrade the LPFP and not the HPFP? That's completely backwards, since the HPFP runs out of fueling capacity far before the LPFP.

I don't see how it could be the fuel pressure sensor.

If you switch to a tune with lower boost and the HPFP doesnt crash i would say that's strong evidence its the HPFP itself.

EDIT: I just realized you said you have PI. If you are going PI instead of HPFP for extra fuel, you need to get that turned on and tuned rather than relying on stock HPFP....

before i turn my pi on my tuner wants the car 100% and no just running 93 and it has crashed on a stage 1 tune
https://www.bootmod3.net/log?id=5fa1...90c6740c921c4e

https://www.bootmod3.net/log?id=5fa1...729b441f87f8de

[thejeremyman9]

Originally Posted by satta535i

before i turn my pi on my tuner wants the car 100% and no just running 93 and it has crashed on a stage 1 tune
https://www.bootmod3.net/log?id=5fa1...90c6740c921c4e

https://www.bootmod3.net/log?id=5fa1...729b441f87f8de

We're back to what i said before then. You likely have an issue with either the LPFP or the HPFP. If there's no additional filters or screens that could be obstructing flow, it has to be one of those two, or whatever is controlling the HPFP pressure. I am not sure how you tested those before. I also don't think you are going to be able to diagnose any further with just logs. The logs will help inform what the issue is (HPFP crash), but when you need to figure out why its happening.

[thejeremyman9]

Another thought/question - why PI in the first place? Do you want full E85? Why not go the tried and true and much simpler route of upgraded HPFP?

[satta535i]

Originally Posted by thejeremyman9

Another thought/question - why PI in the first place? Do you want full E85? Why not go the tried and true and much simpler route of upgraded HPFP?

i took it to a performance bmw shop and they tested everything leak testing etc spent 2 weeks diagnosing it. i had the pi for while, before spool came out with theres. i just did installed it with the ps2 turbo this summer.

[thejeremyman9]

Originally Posted by satta535i

i took it to a performance bmw shop and they tested everything leak testing etc spent 2 weeks diagnosing it. i had the pi for while, before spool came out with theres. i just did installed it with the ps2 turbo this summer.

HPFP upgrades have been available long before that. But anyways, something doesn't add up. In my mind, it's one of these:

1. LPFP

2. HPFP

3. Pressure control for HPFP

If the shop is absolutely confident its not 1 or 2 due to their testing, you should look at #3, which i am less familiar with. You could just be not regulated HPFP pressure correctly so you are 'bleeding' pressure/flow.

[satta535i]

Originally Posted by thejeremyman9

HPFP upgrades have been available long before that. But anyways, something doesn't add up. In my mind, it's one of these:

1. LPFP

2. HPFP

3. Pressure control for HPFP

If the shop is absolutely confident its not 1 or 2 due to their testing, you should look at #3, which i am less familiar with. You could just be not regulated HPFP pressure correctly so you are 'bleeding' pressure/flow.

thats why im thinking its the high pressure fuel sensor as thats the closest our cars have to a fuel regulator

[thejeremyman9]

Originally Posted by satta535i

thats why im thinking its the high pressure fuel sensor as thats the closest our cars have to a fuel regulator

I would just note that your fuel trims pegged at 1.3 suggest you are indeed getting fuel pressure drop.