Having a very odd misfire on cylinders 1 and 2 consistently but no code.
Base map for ST setup with reflex+, 3 port MAC, single bank o2 setup, mac wired to dme. All wiring is triple checked.
Fuel setup: reflex+, ethanol content sensor, right now it has 93 octane only, dual LPFP Walbro 450s with precision raceworks bracket. stock FPR bypassed. -8AN feed with fuel filter, -6AN return. Fuel feed goes in by the back of rail (closest to firewall), reflex pressure sensor plugs bottom of PI rail, fuel return goes from front of the rail to external FPR to LPFP tophat.
It is a fresh build with speedtech 6266 top mount, JE pistons, Manley rods, ARP head studs, VAC cut ring head gasket, BMP intake, 550cc pi injectors, tested index 8 DIs, b58 coils, and new plugs. New seals and spring check/ valve reseated on the head and block was checked, and the rotating assembly was all checked and balanced at a reputable machine shop. All new bolts, seals, gaskets, rings, etc. nothing was spared and no shortcuts. Assembly was done at home not our first build but this is a new platform for me.
All cylinders were compression tested at 150-155PSI across the board when cold and warm.
When troubleshooting and swapping things around please assume that I have already reset adaptations and re-coded injectors every time before starting the car again using MHD and Protool. I also let it idle for a few mins before starting to rev/ check things again.
Also, the motor was primed properly before the initial start-up.
The misfire is noticeable right from the start on cyl1 and cyl2. I had the lower flowing direct injectors (based on test data sent back from the tester) there at first so I swapped them to cylinders 5 and 6, issue stayed. Tested both coils by plugging a spark plug and arcing it with the nearest metal piece and both cyl1 and 2 actually had really good sparks but I still swapped them with 5 and 6 along with spark plugs to see if the issue followed, it didn't. I decided to just reset all adaptions once again and just take it for a test drive to see if anything changes but it sputters really hard through all RPM ranges. you can clearly tell it is misfiring pretty bad. I think my LPFP, HPFP, VANOS, STFT, Lambda, etc all look to be normal to me? which is tripping me. Any help is greatly appreciated.
I should add that on MHD I got codes 2FCA and 2FDA and got a bank one DME mixture control code once but couldn't reproduce it after swapping injectors. However, I have yet to get a specific cylinder misfire.
Only thing I haven't done is continuity test wires from DME plug all the way to each coil/ DI. I have checked them AT the coil and injector and both showed correct voltage. I am at a loss.
I will attach a log from a drive around the neighborhood that might be helpful. I am new to this platform so take it easy lol.
Base map for ST setup with reflex+, 3 port MAC, single bank o2 setup, mac wired to dme. All wiring is triple checked.
Fuel setup: reflex+, ethanol content sensor, right now it has 93 octane only, dual LPFP Walbro 450s with precision raceworks bracket. stock FPR bypassed. -8AN feed with fuel filter, -6AN return. Fuel feed goes in by the back of rail (closest to firewall), reflex pressure sensor plugs bottom of PI rail, fuel return goes from front of the rail to external FPR to LPFP tophat.
It is a fresh build with speedtech 6266 top mount, JE pistons, Manley rods, ARP head studs, VAC cut ring head gasket, BMP intake, 550cc pi injectors, tested index 8 DIs, b58 coils, and new plugs. New seals and spring check/ valve reseated on the head and block was checked, and the rotating assembly was all checked and balanced at a reputable machine shop. All new bolts, seals, gaskets, rings, etc. nothing was spared and no shortcuts. Assembly was done at home not our first build but this is a new platform for me.
All cylinders were compression tested at 150-155PSI across the board when cold and warm.
When troubleshooting and swapping things around please assume that I have already reset adaptations and re-coded injectors every time before starting the car again using MHD and Protool. I also let it idle for a few mins before starting to rev/ check things again.
Also, the motor was primed properly before the initial start-up.
The misfire is noticeable right from the start on cyl1 and cyl2. I had the lower flowing direct injectors (based on test data sent back from the tester) there at first so I swapped them to cylinders 5 and 6, issue stayed. Tested both coils by plugging a spark plug and arcing it with the nearest metal piece and both cyl1 and 2 actually had really good sparks but I still swapped them with 5 and 6 along with spark plugs to see if the issue followed, it didn't. I decided to just reset all adaptions once again and just take it for a test drive to see if anything changes but it sputters really hard through all RPM ranges. you can clearly tell it is misfiring pretty bad. I think my LPFP, HPFP, VANOS, STFT, Lambda, etc all look to be normal to me? which is tripping me. Any help is greatly appreciated.
I should add that on MHD I got codes 2FCA and 2FDA and got a bank one DME mixture control code once but couldn't reproduce it after swapping injectors. However, I have yet to get a specific cylinder misfire.
Only thing I haven't done is continuity test wires from DME plug all the way to each coil/ DI. I have checked them AT the coil and injector and both showed correct voltage. I am at a loss.
I will attach a log from a drive around the neighborhood that might be helpful. I am new to this platform so take it easy lol.
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