Background information. I have a 93 R1 with a streetport running stock twins at 10 psi with the usual bolt ons(catback, midpipe, DP, M2 intake, pettit SMIC, Power FC, 1300cc bored out secondaries). I was driving carefully because the engine was just rebuilt a couple thousand miles ago. I gave it about half throttle and the car had a major stumble/hesitation so I immediately let off the throttle and the car drove fine. I checked the commander and its settings and everything seemed to be in order. I started driving again and upon giving it about half throttle it hesitated again but this time the car lost all power and drifted to a stop and died.

I know , I know, classic signs of a blown motor , but I gave it a compression test and was hitting around 80 psi on all faces (test done on a cold motor). Low numbers but for a streetport it should atleast start with these. But during and after the test I heard a loud buzzing noise coming from under the extension manifold about where the injectors are. It kept buzzing after the car had been turned over and slowly decreased in noise until it finally stopped about 2 minutes later. Any ideas on what this might be? I already checked the plugs and they are sparking. I am currently using the FSM to take me through the removal of the extension manifold and diagnose the injectors but I would really appreciate your opinions.

Thank you for taking the time to read my post.