It sounds like the fuel injection system is not holding residual pressure. Check the fuel pressure with an EFI gauge kit and see how quickly fuel pressure bleeds off after shutdown. The FUEL PRESSURE REGULATOR may be faulty, or not connected properly, allowing fuel pressure to bleed off through the return line.
Jim O’Neill – Chino Autotech Inc., Auto Club SoCal AAR
SAE Int’l SoCal Section Board of Governors,
Vice Chair, Service Technology Programs
NASTF Service Information/Communications Committees
Auto Value/Bumper-To-Bumper CSC Nat’l Council
ASE CMAT-L1, CA. Smog Check Technician
AMI AAM Accredited Automotive Manager