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Old 09-27-2005, 12:31 PM   #14
RiftsWRX
Scooby Guru
 
Member#: 6124
Join Date: Apr 2001
Chapter/Region: MWSOC
Location: Glendale Hts, IL, USA
Vehicle:
2000 NFR AP1 S2000
'07 Honda FIT sport (5MT)

Default

Code:
3373 +17.0 3.8 97 80	00 +15.0 45.8 +17.5 -4.0 400.00 3.5 11.52
3415 +17.0 3.6 96 80	00 +15.4 41.9 +18.1 -5.2 400.00 3.7 11.56
3475 +16.8 3.7 97 80	00 +16.4 46.8 +18.0 -4.4 400.00 3.6 11.68
3599 +17.0 3.9 98 80	00 +15.3 48.4 +18.3 -4.6 400.00 3.6 11.84
3603 +17.0 3.9 97 80	00 +15.2 50.0 +18.5 -4.8 400.00 3.5 11.84
3703 +16.8 4.0 97 80	00 +15.7 48.8 +18.7 -4.9 400.00 3.7 11.77
3728 +17.0 3.9 96 80	00 +15.8 51.3 +18.8 -5.3 400.00 3.7 11.89
Here's the perfect cause/effect relationship.

You can see at 3415 that IDC drops to 41.9. It takes till 3599 for the Tuna to report a sharp rise to 11.84:1. Conversely, at 3475, the IDC shot up to 46.8, but it wasn't till 3703 that you see AFR drop again. That's a few hundred RPM delay in cause/effect, as reported. The important part to note was that the reported fuel offset of -5.2 is similar to the IDC drop reported, in relation to the other rows.

Now...

Code:
5707 +14.7 4.3 95 70	00 +22.0 75.9 +26.0 -6.2 445.00 4.1 11.65
5747 +14.7 4.4 97 70	00 +22.4 73.5 +26.0 -6.3 445.00 4.1 11.65
5941 +14.9 4.3 97 70	01 +22.8 76.6 +26.1 -6.1 475.00 4.2 11.67
5837 +15.1 4.4 97 80	00 +23.9 78.0 +26.8 -6.6 475.00 4.1 11.62
5787 +14.5 4.4 97 70	00 +23.7 77.6 +26.1 -6.1 475.00 4.1 11.61
5827 +14.3 4.4 97 60	03 +24.0 74.5 +14.4 -6.3 475.00 4.0 11.53
6016 +14.1 4.4 97 70	00 +23.7 77.6 +14.6 -5.6 475.00 4.1 11.56
5973 +13.3 4.3 95 70	00 +23.4 76.9 +15.0 -5.8 475.00 4.1 11.62
Invoke that same logic here.

5747 you have a lean out of -6.3 from the -6.2, which caused a 2 % IDC drop. The tuna didn't report the difference, but we know from my last example that a 4% drop in IDC was over a 3/10th change in AFR. That happened ~220 RPM after the fact.

The 1 count also happened about ~200 RPM after that fact.. Yet, the tuna doesn't report a change, when logic dictates there should be at least SOME reported change.

The 3 count at this point I'd imagine is a direct effect of the 3% dropout again in IDC. As for the RPM discrepency, who knows. But one thing is for certain, assuming this all happened in a 200-300 RPM window, I'll take my chances with the cause/effect theory, and the UTEC's relatively slower sampling rate (in comparison to how fast things ACTUALLY happen).

So, in short, I'd try the fuel map changes.

Jorge (RiftsWRX)
www.ProjectWRX.com
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