[BigTurbo_408]

To whom it regards,

This is my first post here and I’m hoping more knowledgeable people can help me with this problem. I have a 6870 single turbo n54 on e50 tuned to 26 psi on Mhd, with most parts you would normally buy to big turbo your car. After doing one or two logs, the car threw misfire codes on cylinder 1 and 2 along with some other codes. I’m hoping it’s just either a o2 sensor issue or maybe just a MOSFET issue in which I have a MSD81 dme for replacement. Not sure if anyone would need or be able to view this log that I took, but it’ll be awesome if I can get some advice. I have attached two screenshots because I am having trouble sending the actual log over via links. The two screenshots of the charts show cylinder 1 and 2 misfiring.

Thank you

[oVeRdOsE.]

define '' with most parts you would normally buy''

what are the steps you did so far ?

could be tons of issue, and of course the one you dont want to see is the DME. Normally DME issue come with aftermarket ignition coils, heat or water damage (cowl conversion).

Can be sparkplug gap, if you're already around 0.020'' , try 0.018''
Can be ignition.

Looking at the code, might be the fuel delivery. What LPFP you have. 26psi on a 68 is serious boost.
also, I dont know why, I tend to see lately more post about HPFP failing. Are you running DI with PI?

Post your log on datazap. Will be easier to check.

Also, who did your map if you're full MHD ? He might help you.

[BigTurbo_408]

What’s up man. This is my parts list. I kind of adopted a second hand project car but the car was well taken care of, was just sitting for about a year and a half.

2008 BMW 335i
Automatic
Doc Race Single Turbo Conversion
99,000 Miles
Factory Options:
Sport Package
Sunroof
2 Key Fobs
I-Drive
MSD80 DME
Engine:
Index 12 Injectors warranty with FCPeuro
Delphi Coils
Bimmerlife R8 Coils with harness - in hand but not installed
CSF Performance Aluminum Radiator
VTT Dual Oil Catch Cans
VTT Valve Cover
ARM motorsport 5" intercooler
Evolution of Speed 1st gen port injection manifold - not installed, no tune
Port injection has not been installed, but I have everything to ready to setup including a split second controller

Turbo System:
Doc Race Kit
Precision Turbo 6870 gen 2
Go Fast Bits Blow of Valve with Trumpet
Exhaust:
Dual straight exhaust
dual resonators in hand but not installed

Tune:
MOTIV Motorsport
Xhp Trans Tune
Revshift Trans Mounts
Fuel-It Dual Bucketless Fuel Pump with Hobbs Switch
Wheels and Suspension:
Megan Coilover Suspension
New Firestone Firehawk Indy 500 Tires 19" Forgestar F14 wheels
Zimmerman Slotted Brakes

Extra Spare Parts:
Carbon Fiber Hood - Original OEM hood on hand.
DME wiring harness
Refurbished HPFP
MSD81 DME
Miscellaneous new parts nots installed wheel bearings, trans guibo, motor mounts.

[lowrydr310]

Originally Posted by BigTurbo_408

To whom it regards,

This is my first post here and I’m hoping more knowledgeable people can help me with this problem. I have a 6870 single turbo n54 on e50 tuned to 26 psi on Mhd, with most parts you would normally buy to big turbo your car. After doing one or two logs, the car threw misfire codes on cylinder 1 and 2 along with some other codes. I’m hoping it’s just either a o2 sensor issue or maybe just a MOSFET issue in which I have a MSD81 dme for replacement. Not sure if anyone would need or be able to view this log that I took, but it’ll be awesome if I can get some advice. I have attached two screenshots because I am having trouble sending the actual log over via links. The two screenshots of the charts show cylinder 1 and 2 misfiring.

Thank you

It's difficult to tell with the table. Can you post the actual logs so we can see all the parameters? I don't want to guess. You didn't mention anything about plugs or coils - what plugs are on there, how old are they, and how old are the coils? Easiest thing would be to swap #1 and #2 plugs first with two that aren't misfiring then do another log. If still seeing 1+2 misfires swap the coils next.

Might sound dumb but you know with the bucketless pump you shouldn't run it under 1/4 tank right?

Likely unrelated to your misfires, but you might want to consider upgrading that intercooler. From what I know that 5" IC is a bit undersized for your massive turbo with 26PSI. Everything else looks good. sounds like a nice project! Makes me want to upgrade.

To upload the log use datazap.me and post the link here.