[N54andrew]

Been having fueling issues with my n54 if anyone can help, car is tuned on a custom map, I replaced hpfp and lpfp sensor and ekpm module, I have a stage 2 walbro 450 pump that sat in e85 for about a year in my old 335i, I don't know if that ruined it or not. Any help is appreciated, tuner said fueling is not enough at higher rpm, car bucks and misfires at 3k rpm flooring it. I also get 2aaf fuel pump plausibility code.

https://datazap.me/u/n54andrew/335i-e92-fueling-issues?log=0&data=3-5-13-20-21&zoom=26-96

[N54andrew]

Bump

[jadams161]

Misfires tend to be plugs and coils. If the plugs and coils are old then they need to be changed. Tuning will almost immediately cause plug and coil issues. Did you replace the fuel pump regulator/filter in the left side of the gas tank?? Plausibility is generally linked to the old style/ faulty LPFP sensor on the fuel rail under the intake. There is an updated unit.

The log shows good LPFP pressure.

When you do a log you need to have all standard boxes checked and add "fuel mode". Do a log in 3rd gear. DSC completely off, rolling in 3rd (manual mode) at 30 mph and push pedal to the floor. Hold until about 6k, shift to 4th and let off.

[N54andrew]

Originally Posted by jadams161

Misfires tend to be plugs and coils. If the plugs and coils are old then they need to be changed. Tuning will almost immediately cause plug and coil issues. Did you replace the fuel pump regulator/filter in the left side of the gas tank?? Plausibility is generally linked to the old style/ faulty LPFP sensor on the fuel rail under the intake. There is an updated unit.

The log shows good LPFP pressure.

When you do a log you need to have all standard boxes checked and add "fuel mode". Do a log in 3rd gear. DSC completely off, rolling in 3rd (manual mode) at 30 mph and push pedal to the floor. Hold until about 6k, shift to 4th and let off.

Here is the new log! I replaced my hpfp and lpfp sensor with a used working one, not the new style though, my tuner was saying fueling is the issue but is fueling fixed now?and maybe my misfires are caused by spark plugs? I should be around 520 whp should I switch to 2 step colder spark plugs? He said fuel rail pressure was bad before
https://datazap.me/u/n54andrew/fueli...og=0&data=3-21

[N54andrew]

Bump

[jadams161]

I am not sure why your accelerator pedal position is not constant...do you have traction control on?? You need to hold the dash button for 10 seconds to turn it off. towards then end of the file you go into fuel mode 15, that is cutting fuel to injectors probably due to having bad spark plugs and coils. You can't tune a N54 without doing the proper maintenance.

The LPFP sensor has to be replaced with the new one for the shadow code to go away.

[N54andrew]

Originally Posted by jadams161

I am not sure why your accelerator pedal position is not constant...do you have traction control on?? You need to hold the dash button for 10 seconds to turn it off. towards then end of the file you go into fuel mode 15, that is cutting fuel to injectors probably due to having bad spark plugs and coils. You can't tune a N54 without doing the proper maintenance.

The LPFP sensor has to be replaced with the new one for the shadow code to go away.

I did have traction control off, not sure why it's saying my throttle isn't consistent? Odd and okay ill get a new lpfp sensor and replace the spark plugs with 2 step colder and new coil packs and see if that makes a difference, I really appreciate your help ! Seriously!!

[jadams161]

Originally Posted by N54andrew

I did have traction control off, not sure why it's saying my throttle isn't consistent? Odd and okay ill get a new lpfp sensor and replace the spark plugs with 2 step colder and new coil packs and see if that makes a difference, I really appreciate your help ! Seriously!!

You don't need 2 step colder plugs for stock turbos. I run the stock Bosch plugs in my stage 2+ custom tuned n54. I have tried all the NGK plugs and found the Bosch run best for me.

[jadams161]

Look at one of my logs. The throttle and accel pedal pos are relatively constant throughout the log.

https://datazap.me/u/jmadams/wedge-v...data=2-3-21-24

[N54andrew]

Originally Posted by jadams161

You don't need 2 step colder plugs for stock turbos. I run the stock Bosch plugs in my stage 2+ custom tuned n54. I have tried all the NGK plugs and found the Bosch run best for me.

Thanks again Adam! I'm running upgraded turbos from daw turbos! I should be pushing around 530whp from what my tuner tells me! So exactly why I was wondering if I needed 2 step colder

[ctuna]

https://www.e90post.com/forums/forumdisplay.php?f=378

[jadams161]

Originally Posted by N54andrew

Thanks again Adam! I'm running upgraded turbos from daw turbos! I should be pushing around 530whp from what my tuner tells me! So exactly why I was wondering if I needed 2 step colder

With upgraded turbo I would start off with NGK one step colder and see how it runs. The stock plugs are only good on lower HP engines.

[N54andrew]

Originally Posted by jadams161

With upgraded turbo I would start off with NGK one step colder and see how it runs. The stock plugs are only good on lower HP engines.

Thanks again adam! Here are the new logs with the new spark plugs!
No more half engining or misfires popping up but still get a weird jerking around when I am completely on it in the higher rpms! Would a slipping transmission cause this??
https://datazap.me/u/n54andrew/fueli...og=0&data=3-21

[jadams161]

Something isn't right...you don't show full throttle until almost 4k rpm. The car goes into fuel mode 20, not sure if that is lean?

[Sgop335]

fuel mode 20 is called spool mode, which is normal for most n54 below 3k rpm.

there are some strange things going on in that log.
Boost is dropping very abruptly twice. Not sure why.
bank 2 spiked lean at high boost making the rpm stumble
the rail pressure (hpfp) is also tanking around that time.
also has torq limit 4, but that is another issue

[N54andrew]

Originally Posted by Sgop335

fuel mode 20 is called spool mode, which is normal for most n54 below 3k rpm.

there are some strange things going on in that log.
Boost is dropping very abruptly twice. Not sure why.
bank 2 spiked lean at high boost making the rpm stumble
the rail pressure (hpfp) is also tanking around that time.
also has torq limit 4, but that is another issue

I have codes for both secondary o2 sensors would that cause anything? And I did get 30fe code as well

[N54andrew]

Originally Posted by jadams161

Something isn't right...you don't show full throttle until almost 4k rpm. The car goes into fuel mode 20, not sure if that is lean?

So that would be a fueling issue?

[N54andrew]

Originally Posted by Sgop335

fuel mode 20 is called spool mode, which is normal for most n54 below 3k rpm.

there are some strange things going on in that log.
Boost is dropping very abruptly twice. Not sure why.
bank 2 spiked lean at high boost making the rpm stumble
the rail pressure (hpfp) is also tanking around that time.
also has torq limit 4, but that is another issue

Here is another log!

https://datazap.me/u/n54andrew/fuel-...&data=2-3-9-21

[N54andrew]

Bump

[Sgop335]

Originally Posted by N54andrew

Here is another log!

https://datazap.me/u/n54andrew/fuel-...&data=2-3-9-21

Look at rail pressure, its low.

[N54andrew]

Originally Posted by Sgop335

Look at rail pressure, its low.

Any recommendations?

[Sgop335]

Couple options hpfp replacement or lower ethanol map if that helps etc.