Are you sure that you got a good tank of gas when you filled it up last?
I can see the knock occurring in 3rd more than 1st or 2nd because there is more of a load on the car at higher speeds.
Throw a can of octane booster in it to see if it goes away?
It could be the exhaust, but a can of octane booster is a quicker check! No KR on the 1-2 or the 2-3 shifts?
Yes I have been filling up with 91 octane for almost a year....that is what the previous TT chip and the newest TT chip was set to.
I will still try the octane boost .
I took the car out today after getting the TPS and IAC readings set perfectly. At operating temp (closed loop the IAC readings were were low...under 10..... the TPS was set at .42 and WOT was 4.62.
On the drive When I punch the pedal and it shifts from.1st to 2nd and than to third....there is a knock right before it shifts.....about 1 - 2 on the scan master. When I am doing regular driving amd it shifts through he gears there is no knock...stays at 0.0.
I was thinking there may not be enough fuel delivery in WOT (lean). So I changed my MAF Translator setting on the WOT knob to #1....which was 2% Rich at WOT.
I did a once over on all the vaccum lines as well and zap strapped them all. I ordered a new gasket for the vaccum block as well.
I even loosened up the exhaust and moved it away from the frame rail.