So last week's Seattle dyno day was a fun get together. Some high five and some disappointment.
I took away more than my plot of whp, torque and afr. The question kept being asked, why was I running so rich and misfiring at the upper revs?
With the new larger turbo compressor thus higher lbs of air delivery how was I going rich? It just did not add up.

Time to study the data log. My original thought was to go into the fuel map and lean the appropriate cells. As I carefully looked at the data I saw the water temperature swing drastically cold when we went WOT. On the order of 120 degrees F. This really honks up the fueling as there is a temperature compensation table. In essence I had the "choke" on while running WOT.

I have a hardware problem not a software/ tuning issue. I decided to replaced the sensor. While doing that I notice the two pins did not look even on the plug. I took off the harness boot and gave the wires a light tug. They pull right out with very little effort. The tangs on the Amp junior timer were not engaging the plug connector body.
The wiring will get you every time...

From a good friend and fellow car motorhead:
" I'm impressed that you were able to diagnose the problem using your data log. As you point out, the ECU operates on that data in real time, and can calculate the wrong answer as fast as the wrong data arrives!
>
> I could imagine that the ECU designers would have done well to filter that kind of data with a long time scale. In this case, water temperature is only used to infer the temperatures of the intake runner, intake valve, and combustion chamber, thus compensating for their affect on the fuel evaporation. These don't change by 100 degrees in 10 milliseconds!! If such a filter were in place, it could have fueled properly, even with the intermittently noisy temperature signal."

Back to the data log.
Conclusion, garbage in equals garbage out. You can see a direct relationship between the water temperature and the fuel pwm in ms. Looks like there is not a filter employed to ignore wild swings in engine temperature.
Again this is my EMS. Not sure what the Saab T5 does, but either way it is always wanting water temp data.

I figured I would share with the forum since some of you are into engine management.

Why do you think that was happening just at WOT? The vibration?

Good find, does it drive better now?

I think it was the fact the high engine vibration or torquing pulled on the wire bundle enough to pull it away from the contacts. After the run it returns to normal. I have not gone for another test drive with the datalog running. I need to do that to see if I corrected the problem. But as a daily driver no issues.

engine management?

I'm into it