Phantom knock with 5EAT trans

Was out tuning last night and keep getting an intermittent problem. shifting manually in sport mode in third and fourth gear right around 5500rpms I get a knock. when in full auto mode this does not happen. Was wondering if anyone has had this problem or some insight.

 

Also for starters, it did it even when we pull timing so its not an actual spark knock. something is causing it. The main reason I am leaning toward the tranny is it only does it while manual shifting.

If you see the knock go up on knock sum, it's probably phantom knock, native to 5EATs.

 

If it's on FBKC, or FLKC, then, it only still might be worth checking out. How much timing is being pulled by the ECU? How much are you pulling and how?

yup, had EXACT same issue (only if manual shifting). it is NOT the trans (in fact, had a mate have exactly the same issue in his manual through an entirely different tuner) I had the issue (over a period of 3 months, testing everything possible) when tuning with dave @ cryo. We basically started the tune again and Dave "tuned it out" slowly but carefully. He maybe able to pipe up and add what he thinks the issue may have been (although because we just bit the bullet and started again, we may never know)

 

 

oh and here's the thread you want to read... http://legacygt.com/forums/showthread.php/stumble-stutter-thread-182559.html

MrTris- not sure how much timing but i know we took more than the factory map takes and still getting it so I know its actually phantom knock. Not sure if I can go up on knock sum as I am only tuning with open source. Its just seemed like a trans thing as it only does it when manually shifting. 3rd and fourth gear only as well. I suppose we could go back to square 1. I would say I only have a light stage 1 tune.