any ideas what could cause or fix this??

[DDSR240]

Well my car was breaking up on the dyno when I went for my tune my so we tried a new walbro..no dice so instead of paying them $80.00 times? hrs i desided to bring it home and and try to figure it out well first I checked all the nessecery checks like boost leaks, installed a fp gauge that checked out, cheked the batt. that was good also, checked all grounds and the resistance was like .3 beetween the motor and chassis and all the eccs grounds checked out too exept one on pin 38 or 39 that read .5. Now what I have found out is that when the aem unit is hit or tapped my fuel pump relay clicks and if I tap the aem while the car is running it will shut offinstantly and before the motor completly dies the tach drops to 0. So then I checked to see if I still retianed power to my injectors and coils when the car dies and I do. Now all I have to do is cut the car off and crank it back up and most of the time it will run fine other times I can't rev the motor past 3000or someimes 5.5 and sometimes 7.5 and my favorite 9000 ond all I do is cut the car off and then back on for the rev limit to change. the funny thing is that I sent the ecu back to aem to get it looked at and they said it was fine this was about 4 months ago when I thought the ecu was why my car wouldn't run. If you want you can go to youtube to see a video of it running great .http://www.youtube.com/watch?v=q5NfKM_GKyY