fuel trims stuck at 100% could this be the MPI relay?

[Stainbox12]

ok, so i just got my logger, hooked it up, checked some codes, and im throwing the number 31 (knock sensor) im about to replace it, but i found out that my fuel trims aren´t moving at all, they are stuck at 100% all the time, my o2 sensor works fine apparently, so my coolant temp sensor. a while before i got the logger, i found out that the car wasn´t starting, i began diagnosing it, and i found that the fuel injection wasn´t injecting any fuel, though, i had spark, the pump was ok, and so on, so the problem was that the fuel injection system wasn´t getting any fuel, i jumped it, with some wires from the battery directly and it started, so i was told this could be the MPI relay or the fuse, the car has been working fine with the wires from the battery to the fuel injection harness, but could this cause the fuel trims to be at 100% constantly without moving?

thanks for the help!!

 

[timloomis]

well the mpi relay(behind your radio) will not turn on the pump if its bad.i had that problem a while ago.when you reset your ecu,the trims automatically go back to 100 untill you drive for a while.how longs it been since you unhooked the ground?