I have a 2015 Camaro SS with a large-ish cam. I paid for an initial remote tune, then I re-tuned it several times as I added more bolt-ons. It ran great, but I wanted more power and added small twin turbos, bigger injectors, ZL1 fuel pump, and swapped long tubes for shorty headers. I got the new injector data in without issue, and then took a long break because of work and life. I finally got it running and am starting to do the actual tune, but I have several odd issues. Since I am new to forced induction (and still consider myself a novice tuner), I am reaching out for help.
So I did some preliminary MAF scaling sitting in the driveway, then I took it on the road to get some MAF O2 Error readings in the higher register, and just a short hit to make sure it was making boost if AFR seemed safe.
As I turned out of the parking lot after turning on the scanner, I could feel a slight miss, which I think (if I'm reading this correctly), is because bank2 is running lean (around 1-2 seconds in). Quickly after both sides went lean because of MAF scaling, which I expected.
As I started on the highway at about 7 seconds in, it actually began pulling timing, I'm guessing because bank2 was lean and it was knocking. It can pull up to 8 degrees at that point, but it only pulled 6.
I just cruised down the highway and it seemed to continue a real slight miss, so I didn't bother trying to do a steady(ish) slow log in 4th.
At about 5:22, I came to a place to turn around and the miss felt like it cleared up. I was not watching the laptop and driving so I couldn't see the readings, but the wideband looked safe enough.
So I did a moderate pull in 2nd to see if it was building boost. I only planned to rev it to about 5,800, but right before I got there, it suddenly lost power for a fraction of a second. I could hear what I think was the BOV venting to atmosphere (at 5:35), then it resumed running as before.
I cruised the rest of the way home and it seemed to run about the same as before the pull.
When looking at the log, note that my WB is in the driver's side exhaust pipe, about 12" after the turbo outlet.
So my first question is this: I don't notice the miss when it's cold. Has anyone had new injectors behave badly only when hot, or is it possible it's something else? I plan on pulling the plugs tomorrow to see if I can isolate the problem to a particular cylinder, then try swapping that injector with another cylinder. Again, it seems to run fine cold, so I'll also take a quick log from a cold start up and verify that.
The next question: do you have any idea what happened when it got to about 5,500 to cause it to fall on it's face? There wasn't significant KR at that time (just about 1 degree even though it pulled 6 getting on the highway), so I really don't think that was too lean, but I can't think what else would cause that.
The last question: once the miss is resolved, would you just continue with the MAF scaling and spark adjust and then move onto the VVE, or would you do anything different? I'm open to doing a SD only tune, but if I can use it the way GM intended, I prefer to.
As a side note, and I believe this is unrelated, my Ambient Temp reading is way off; it was actually about 80F outside, but it showed between 30-36 when I was sitting in the driveway and only 32 during this log. I'm guessing something happened to it when I removed the front bumper. I understand it isn't used in any tune calculations, but it is odd and is returning values, so I wanted to mention it.
Thanks in advance for reading this and looking at the files.
2015CamaroSS_NewInjectors_NewMAP_CatsOff_InitialMAFScale.hpt
2015CamaroSS_OperatingTemp_HighwayCruise.hpl
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Originally Posted by 01SLPSSM6
