OK something's not right. The couple times I jumped on it on the way into work the PE AFRs were in the 10s which is what I would expect to see in this cold air. Since I brought the laptop in with me, I'll snag a quick log on my way to my neighbor's shop after work.
1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
2004 Corvette Z06 with longtubes.
That's weird. When I looked at your log and I saw you going lean in boost I thought your fuel pressure regulator is not referencing boost. I'll take a closer look at your log now and see if I can figure out what's going on.Originally Posted by Supercharged111
It gets better. My AFRs under boost seem to vary from one mile to the next. I'll jump into last night's log too and see if I can spot a pattern. I will say that idle and cruise AFRs seem more consistent MAF only. I did learn some stuff about the transient last night and have to wonder if that corrupted some of the data I got last time I tried fixing VE and MAF. Among the other stuff I'd gotten wrong.
1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
2004 Corvette Z06 with longtubes.
Okay, I've had a proper look over your log and I've determined that your wideband is toast.
No shit? Narrowbands look good? Just need a new WB sensor? Truth be told it's 10 years old.
1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
2004 Corvette Z06 with longtubes.
No shit!.... when you're in boost and your wideband is reporting in the 13's and once in the 15's, your narrowbands are always in the 900's. Looks like you're not running lean in boost after all.
Ugh, I was wracking my brain because the MAF was reporting consistently but the AFRs disagreed and I didn't know who to trust. I'll let you know when I have a new sensor on the truck. Hopefully it only takes a few days to show.
1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
2004 Corvette Z06 with longtubes.
I can't use the last log... you'll have to run another log for me when you've got the new WB sensor. 18,000 frames was good. I need minimum 12,000 but anything over that is alright.
I can easily redo the 18k route with a new sensor. How were the transients, gear changes, all that? I didn't choose a route where I could really load it hard WOT in 3rd gear, rather something that better resembled my my daily routine but pulled the shifter back to 2nd and 3rd a lot to better populate the mid range cells.
1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
2004 Corvette Z06 with longtubes.
The more MAF cells you can hit, the better. Try to get one low gear pull to at least 5000rpm if you can. Load isn't important when you're at high rpm, it's the airflow that's important... and at 5000rpm with the throttle open you get lots of airflow so you hit those higher MAF cells. I only really need one of those, so the rest of the log can be your normal driving... just try to get a couple of harder decels in there as well.
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