$8D, 1227727 (basically 1227730) ECM.
I'm tuning WOT VE using my wideband, and I noticed that my AFRs are pretty inconsistent. For example, in one evening I had three WOT pulls, and in three identical cells (5250rpm, WOT) the datastream reported a target AFR of 0.830 (12.2). However, my wideband measured AFRs of 0.762 (11.2), 0.794 (11.7), and 0.857 (12.6). I looked at injector PW, and they're significantly different - 7.2, 7.3, and 6.8ms, which correspond with my wideband readings.
How is this possible? I understand many factors go into fuel calculations, but almost all of those should be reflected in target AFR. I can't think why injector PW wouldn't correspond with target AFR for a given VE cell. BLMs are slightly different (which I don't get, because BLM learn should be disabled in PE mode), but their differences are minor (133, 128, 129) and don't correlate with the injector PW differences. The third sample is at a higher coolant temp (101 vs 88 for the first two) and a lower air temp (35 vs 60 for the first two). However - again - fueling changes related to CTS/MAP should show up in target AFR, I'd think.
The only thing I can think of that might affect injector PW without affecting target AFR is acceleration enrichment. I've been trying to read up on that (thank you to 84Elky for the amazing summary document!), but it's pretty heady. At any rate, the latter two data points are both about 5-6 seconds into the acceleration run, so I'd think AE would have died out by then.
What am I missing?
I've attached an Excel sheet with the WOT data from the two runs. The 5250rpm rows are bolded.
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