My thoughts-- it's either the injectors, fuel pump or both. You aren't anywhere close to reaching the duty cycle of the stock injectors or the fuel pump.

Specifically, min pulse width. You haven't done any mods to your car to really necessitate upgraded injectors / pump so my guess is that it's dumping way to much fuel into the cylinders at low RPM.

 

^^
Might be right if the tune doesn't compensate for the fuel mods correctly.

Can you log knock? It looks like the MAF is fluctuating a bit in that range but the resolution is pretty poor. Timing isn't being pulled though so it doesn't appear to be knock.

I'd remove most of the NB O2 stuff towards the end of the files. Monitor, Voltages, evap, all that crap can go. Not sure how your tuner software works but that might help increase signal frequency if you remove some signals.

Also, can you do a full pull from 3000rpm to redline, going WOT immediately (not slowly going into the pedal)? 3rd or 4th gear.

 

Assuming o2 voltage is the same as what I'm used to seeing on other cars, it looks like it was pegged before the stall very rich. I don't think your injectors are tuned for correctly or your fuel pressure is too high at the rail (bad FPR?).

Still leaning towards your tune not being right. Don't throw more parts at it unless they're your stock fuel pump and injectors.

 

This is what I was saying too.

If he just punches it I want to see where the numbers go.
It does look rich from the voltages of the O2's but its hard to say because hes easing into the throttle it seems.

 

on the graph, I am in 4th gear cruising at 4000 RPM.
I then tap the gas pedal (while it fully released, cruising), and let it out
I continue to tap, 4100, 4200, 4300, 4400, then at 4500 WHOA!!

not sure on how the maf is supposed to react, but I'm very interested if you happen to know..

I did notice timing drops considerably when the car "wakes up" from this low end limp mode it seems...

 

I agree here. The injectors have long been a suspicion for me...or the wiring harness connecting them..

fuel pump was just replaced with a 255lph walbro. I have suspicions in regards to the little regulator/dampener thing that's attached to the fuel sending unit assembly in the tank.

Last but not least, would a cracked fuel line produce these sysmptoms? The car drives better when the fuel tank is full vs when it is towards empty(tons of hesitation, car feels heavier, and loses power)

Let me know if you want me to log anything else, I wanna do a few more runs this week..

 

The tune is good as far as I saw on the Dyno/sheets(which I still cant find for Jimster).

I'm looking on Cipher everywhere for knock sensor, but can't find it. any ideas? when on dyno though, I saw the flat line on top of each point point, indicating no knock all the way through till top speed.

I'll take those signals off for the next run. Hey quick question, If I log the abs wheel speed sensors, would their be any way we can tell if they are in spec per the mph/RPM or something like that? I have a huge suspicion that if this isn't fuel injector/regulator/line related, these may have something to do with the issue, because after i changed them, the car drove much better responsiveness wise.

Yeah I'll drop the pedal in 3rd and 4th as fast as I can from 3kRPM (Who knows, maybe I can get that P0303 or equiv misfire code to flash again if it drives long enough out of spec)

 

I was thinking it might be the regulator(dampener) that connects to the rail directly or the little one connected to the fuel sending unit assembly in the tank.

yeah, I can't throw more money if I wanted to..but I'm here so I dont have to. Something keeps telling to go back down to Connecticut already, and just take the 150/hr hit or whatever the hell they are gonna charge..

 

I'm gonna do another handful of runs this week.
slam pedal 3k rpm to redline in 3rd and 4th.. wtih tc, and without tc
removing all the extra nb02 monitor, evap, heat switch, etc, from cipher log

Any other parameters you want me to log that might benefit us?

Thanks again everyone...it would be awesome if this problem can just get F'n fixed already...This has been over 2 years of people telling me to get rid of this car now...oh and disappointing subarus everywhere...they always want to race for some reason...

 

If there's pedal position and throttle position (in %) instead of the voltages, those are a lot more helpful.

 

i'm wondering myself about the injectors. PW specifically of the 2008Z vs 2003G. Why the decision to use the 2008 instead of just rebuilding a set of 2003? May not even be the same impedance.. anyone have the figures on that? Not out of the question for generational differences in injector Ohm impedance.

 

When I was having E tunes sent to me direct from UpRev down in Arizona, one of the head techs sold me his old maf/injectors that he replaced with better ones to support his 08 370z TT build. So I figured , hey let me swap these and see if any difference is made(the number 3 cylinder has been a problem with both sets of injectors, which leads me to think the wiring harness may be to blame, or just really really bad luck with injectors) Also, I've listened to each injector, and cylinder 3 always sounds like it ticks slower. I'm unsure on the differences in impedance also...

 

Okay, I will try to get those values, not sure if Cipher offers, but I will dig. I'm still learning this stuff, but I'm good with computers, so I should find it if it's there...

Here are the values that UpRev asks for to Etune just fyi...
A/F CORR
-
B1 (%)
A/F CORR
-
B2 (%)
AFR WB
-
B1 (AFR)
AFR WB
-
B2 (AFR)
ACCEL PED POS 1 (V
-
Accel)
B
-
FUEL SCHDL (ms)
CAL/LD VALUE (%)
COOLANT TEMP (F)
ENGINE RPM (rpm)
IGN TIMING (BTDC)
INJ PULSE
-
B1 (ms)
INJ PULSE
-
B2 (ms)
INTAKE AIR TMP (F)
MAF GM/
S (gm/s)
MAS A/F
-
B1 (V)
NB
-
O2 SEN 2
-
B1 (V)
NB
-
O2 SEN 2
-
B2 (V)
T
HROTTLE POS 1 (V
-
Throttle)
URBINE REV (RPM)
(Automatics only)
VEHICLE SPEED (mph)

 

How is your spark plug in piston 3?
I also have a problem in Piston 3...

 

Its rough, carbon fouled after driving for about a week installed new everytime.. Changed em almost 6 times now over the past 2 years

Whats goin on with your 3cyl? Are the plugs discolored ?