I have an Icarsoft LR V3. It was reading in the 70’s ignition on engine off, high 400’s to mid 500’s when idling and around 2100 when on the accelerator. It would run smooth right until dying, no misfires detected.Sure doesn’t sound like a timing chain issue from your description. What kind of scan tool are you using? When you read fuel pressure, is it rail pressure (high pressure) or the low pressure side of the system? When it runs (before dying) is it running rough or smooth?