I'm swapping a 5.3L / T56 into a E39 BMW. It will be turboed but for now the turbo is off and I'm just trying to get it started. I had a local shop do a base tune on the car and it didn't start. Well it would start fine but then immediately die about 1 second later. Almost like fuel is being cut and its consistent every time. I thought maybe vats so I took it back to the shop. They said they tuned for 2 bar and I put a 3 bar sensor which caused the issue. Well does the same thing. I bought HP Tuners since its a pain to drive to the shop every time. Hoping someone can take a look and see if there is anything obvious?
I have a fuel pressure gauge on the car so its not a fuel issue. Only code I get is for EVAP.
2000 5.3l Engine
Deka 80 injectors
3 bar MAP
No MAF
LS6 intake
DBW
IAT and oil pressure is not hooked up