I have a 97' baja 272 with mpi502 just recently the motor will die as if it is not getting fuel,after waiting a while or sometimes trying to restart the boat ,giving it some throttle it will start again. I pressure tested the high volume pump and it shows 35psi . What does the lower lift pump do and could it be a issue, if it is not workin up to par ? Any advise would be great .Thanks Tman 365