What should I check to be the issue? No matter what I add for fuel there it wont go away, could it be a faulty wideband? I'm not getting a misfire there either.
Mods:
BBK-B
FIC 1450's on e85
DIY Coil on Plug
Single walbro-unmodded
Kelford 272's
ETS 4" FMIC
Injen LICP
Crushed IX BOV
3 inch TBE
LC1 wideband for AFR's

Here's a screen shot:

 

If it's a single pump system still it could be overrunning the pump. 330 load seems a little low to be running out of fuel, but It's possible. what's the IDC at?

 

I'm having a similar issue with my setup on pump gas so I'm curious to see if you get this resolved. However, I have been able to correct it for the most part by adjusting my fuel map in that area. The only problem is that my fuel map looks like someone dug a hole in the middle of it and it doesn't look very pretty, which makes me think that it could still be a mechanical issue.

 

Injector Duty was at 84% I think?

 

At that RPM range for that turbo the pressure on the turbine is still quite low, yet 30 psi is behind the compressor. During valve overlap the fuel mix just goes out the tailpipe and the WB reports it like a lean miss. Adding fuel will just make it worse. Once back pressure builds up it dissappears. On small stock turbo's the opposite happens because backpressure is so great causing internal EGR.

 

It didnt do it when it was first tuned though? although I was running 29psi, it does it now even at 20psi though, that was interesting though.

Is there anyway I can test this or fix it

 

Have you had the fuel pump on there for long??

If it does the same at 20 psi, its not the pump.

If you think the map is correctly tuned, then I would run down the checklist of possible fuel system issues, ie: dirty inj, nasty filter, pump life etc etc...

 

I actually just had this happen for the first time too. Its 'tunable' but very uncommon. Zero boost leaks up to 40psi, DW300 fuel pump with MSD boost-a-pump and fuel pressure is solid (checked with gauge). ID1000 injectors at a max of 95%IDC (resistor pack bypassed), running 96530706 rom. The only thing we haven't tried are new injectors thus far.

 

This is pretty much how my map looks, although the drop isn't as drastic.

 

On of the local shops tuners down here just had this problem on his car today too, he switched to e98 did a pull, it was flat, did another pull and it was present from then on out in the following pulls. His starts a little earlier and lasts a little longer though.

 

Anybody have an idea? I logged voltage and it only drops to 13.7 so not enough that the fuel pump cant pump fast enough

 

Unless you did a fuel pump rewire, you aren't getting that much voltage on the stock wiring harness at the pump. On average I see closer to 12.2v back there.

At 12.5v and 30psi of boost, the wally only flows about 189LPH.

 

Thanks for that bit of info, I havent done a rewire. I was only logging to see if overall voltage was down I guess, I didnt think about fuel pump voltage. Maybe i'll rewire it and see if it goes away.

Minnesota already switched to e70, so i'm going to do another log tomorrow and see if its still there. If so i'll try the rewire

 

In that case it probably isnt the reason then, unless cams settings have been changed. I have a different turbo but I get a brief lean spike right before peak boost that is definately not related to the actual ratio of fuel to air. It goes 13:1 but is brief and not worth worrying about.

 

I was also only on 29psi then, i'm at 32ish now, I'll turn the boost way down today and see if it goes away.