Some may remember my previous post regarding the surging felt on my 08 Type S 6mt during normal acceleration mainly felt in 2nd and 3rd gear. I have still had no luck figuring out what causes it, but im making this post because the temps actually got pretty low in the Chicago area tonight. As I was driving home from work I was pleasantly surprised by for the most part smooth acceleration. The outside temperature was in the 60's and the car hasnt felt this smooth in a long time. I have been trying everything I possibly can on my own to figure this out because its been driving me nuts. So much so that I have been looking for another 6mt Type S to buy.

I have tried the following:
-new plugs
-new coils
-tried multiple IAT sensors
-replaced APP sensor
-swapped map sensor
-swapped EGR valve
-ran fuel injector cleaner
-ran 100 octane fuel to eliminate detonation or knock retard
-drove with 02 sensors, knock sensor, EGR valve, IAT sensor disconnected individually) to see if driving charecteristics changed at all
-did some clutch tests to ensure no clutch slippage
-tried multiple brand of 93 octane fuels

Things that have me wondering but im unable to test or swap out are fuel injectors, main ECU, new 02 sensors (vs just driving with them disconnected), ensure catalytic converters are good, motor mounts (which visually look fine).

So with all that said it now leads me to my main question. After driving tonight and confirming that the car accelerates relatively smoothly with mild outside air temperatures (60's), what system/component/sensors on our 3G TL's can change the driving charecteristics so that the car surges/hesitates during normal acceleration? Its got to be something that when it gets warm or hot causes this. I have driven other 6mt Type S's that did not do this and some of my test drives were on 90 degree days.
Lastly, the good thing is since it seems my car is capable of smooth acceleration on cooler days that would eliminate a lot of things. For one I dont see the clutch having anything to do with it, or engine mounts as those should be relatively uneffected by a little cooler air.

Looking for all the input I can get as I REALLY want to keep this Type S, but if I dont figure this out I dont think I can get over a car that lurches your body a little as your trying to accelerate normally. "I Hate Cars", "nfnsquared" im all ears!!

Thanks again,
James