Can't seem to get rid of CEL code P0089. Replace the pressure sensor on the end of the fuel rail, but error remains. Sometimes it will stay away for a drive or two, but always seems to come back. Randomly, the fuel pressure will spike in the ECM reading up 10 psi or so at idle, but the manual gauge stays constant (which is why I thought it would be the sensor). Not sure where to turn now...filter, pump, leak somewhere??? Any suggestions would greatly be appreciated.