Injector pulsewidths different in boost, bad inj?

I was close to having my TBSS tune finished (just had a rough spot around 60% throttle), and now and all of the sudden it sputters bad once it gets over about 6psi. Wideband shows some lean spikes, but I`m not really even getting any KR (less than 1*). I noticed on one of my sputtering mid-throttle pulls, that the injector B2 peaked around 19 while the B1 injector continued to climb to around 24. But in the same scan I did several boost pulls, and it sputtered on all of them, BUT only on the last pull (frame 7,700) did the pulsewidths differ from each other. It runs great from idle up to about 5psi.
I did try reverting back to tunes that I know did not do this sputtering deal, and that didn't fix it, so it seems like a hard-part problem to me.

Any thoughts?

Here is my tune and another log of the unequal pulse widths. If it is actually in open loop then there should be no reason in world for it to make one bank leaner than the other, right? I just noticed that the O2 sensors are indicating that the bank 1 is going lean. The bank 1 injector is the one that continues to climb higher than the other. So are bank 1 injector and bank 1 O2 sensor actually referring to the same side of the engine?

bump

Ok, so what is going on, did I tick you guys off somehow? Why is nobody responding?

When a fuel system can`t keep up, is it common for only one bank of injectors go lean? Specifically the bank that is the "end of the line" in the fuel system?

I wonder if I`m just loosing fuel pressure (no gauge). Fuel pressure was perfect on the dyno a couple months ago though.

Man, to get help on this forum is like pulling teeth. Everyone seems to not want to share tbeir knowledge, or they just don't give a f$#&....... GL.

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Originally Posted by monte4ever

Man, to get help on this forum is like pulling teeth. Everyone seems to not want to share tbeir knowledge, or they just don't give a f$#&....... GL.

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i can pay

what about your narrowbands readings?
Maybe you are lean on one side. Check both banks through a wideband.

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Originally Posted by ingsteve

what about your narrowbands readings?
Maybe you are lean on one side. Check both banks through a wideband.

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Yeah man, that's what I was talking about in my second post. The B1S1 O2 sensor starts to read lean as soon as the bank 1 pulsewidth starts to climb higher than bank 2.

You can see what I'm talking about starting around frame 7,700 in the scan in my 1st post.

I finally borrowed a fuel pressure gauge and here is what I saw: Pressure was rock steady @63 psi during regular driving, but when I got into boost where the engine starts to sputter, fuel pressure dropped a little and fluttered violently between about 56 to 60psi.
I have a MSD vacuum actuated "boost-a-pump" that is turned up all the way. It puts out around 19volts while in boost (I checked it to make sure it was not the problem). So I thought if fuel pressure is the problem, then the sputtering should get worse if I turned the boost-a-pump down. After turning the b.a.p. down, the sputtering was the same, and the fuel pressure still fluttered 56-60 just like before.

I have no idea whats causing this mayhem! I still don't understand why the injector pulsewidth can be different from one bank to the other if it is in open loop. I have closed loop disabled, or at least I think I do.

Any ideas?

So it looks like youve got LTFTs turned off. Plotting STFTs aginst the VE table shows that the tune is way off. That should be fixed first.

Bank 1 definitely goes wonky under boost looking at the narrow band mV but I don't know if thats a result of it breaking up or if its breaking up because it's leaning out. I'd try swapping coil packs left to right and see if the behavior moves banks. If not then do the same with injectors.

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Originally Posted by 5_Liter_Eater

So it looks like youve got LTFTs turned off. Plotting STFTs aginst the VE table shows that the tune is way off. That should be fixed first.

Bank 1 definitely goes wonky under boost looking at the narrow band mV but I don't know if thats a result of it breaking up or if its breaking up because it's leaning out. I'd try swapping coil packs left to right and see if the behavior moves banks. If not then do the same with injectors.

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This weekend I finally got a chance to try what you said. I got the STFT's looking a little better, then I swapped coils, then injectors. The problem seems the same and is still on bank 1.
Today I was going about 30mph and I stepped on the gas, it dropped to 2nd and began spinning, then it redlined and hit 3rd and continued spinning until till eventually I figured I'd have mercy on my tires, so I let off. The point being, it ran perfectly. Then not a mile down the road I got on it while going 60mph and it dropped to 3rd and began to sputter as soon as it got spooled up. I have the scan of this whole incident attached. Frame 8900 and 10600. I don't know what the common denominator is with all of this.
Is it starting to look like a ECU problem?

Finally I'm getting some clues!!! Since I've been getting nowhere, I decided to go back to my 1bar map and tune, even though that's how it was setup when this whole problem started.
But NOW, it doesn't sputter!!!!! I wish I could say "problem solved" and move on, but it's never that simple is it?
It's like there is something wrong with my ECU or OS. I didn't bother to mention at the beginning this the post, three strange things that happened when I enhanced to the 2bar.
1. A few months ago it began to not shut off when I would turn the key off. I could turn it off, remove the key, and it would just keep running. I tried everything I could to fix this problem, without success... until I converted to 2 bar, it magically fixed itself!
2. The tranny used to shift VERY hard no matter what I did to any of the shift tables... until I converted to 2 bar, it magically fixed itself! Even though all the trans. tables were the exact same.
3. The AFR is terrible now, across the board (too rich here, too lean there). I know it looked better than this before. And I really don't know what I'm doing with that confusing 30 section chart for VE.

Now that I did a Write Entire back to 1bar, I have these 3 problems, but on my 2bar OS I have the sputtering dilemma.

Does anybody know what is going on? I feel like I am in the "Twilight Zone meets Burmuda Triangle" realm!!! lol

Anyone?

did you ever figure this out ? sorry to dig up an old thread but im having the same issue. on the dyno it was running perfect now breaks up leans spikes. same symptoms as you.