So my original ported 87mm TB died after almost 4 years, it was a ported unit from a reputable vendor. I replaced it with another 87mm ported TB from Soler performance. The new TB is a nice unit, but it is causing some issues with the tune now. I have swapped back to a bone stock OEM 87mm TB and the issue goes away with the bucking and surging. The data logs show the new Soler TB is flowing more air so I would rather use it but I am at a loss as to what is causing the bucking. It only happens at very light throttle input.
Car is a M6, so in the example I will be in 4th at around 2k rpm and going 45mph. You can hear and slightly feel the car bucking a bit. Soler Performance said they think it is a timing issue, I tried moving the timing up and down in the affected area with no change. Is this a Driver Demand issue or a VE table issue?
I will try and upload a log let today, away from the house right now.
Todd