I have a 2006 F250 with 6.0. Having a strange issue. Sometimes the truck will not start, then retry and it's fine. So a little background. I am very mechanically inclined, I am also an Electronics systems engineer in my day job. So I understand everything that is going on on the truck. I have a SCT scanner to log data. I have several charts showing the first try won't start, then turn the key off and on again and it starts very quickly. I have eliminated all the traces that are the same for both starts. The one thing that is different between the no start and fast start is that the injectors have zero pulse width on the first attempt and on the chart (attached), as soon as the injectors open the truck fires up quickly. Its 60'F outside so not glow plug related.

So what I need to know is what enables the computer to open injector pulse width. My ICP is fine and responsive. What is the code sequence to start pulses?


I do not have a gauge on fuel pressure yet.
Some things are done to the truck:
- replaced head gaskets,
- ARP studs
- New FICM at 54Volts.
- Amsoil oil, filter, and 1u bypass and coolant bypass as well.
- larger turbo
-4" exhaust - no CAT
-update kit installed
- high output 300 Amp alternator
-SCT tunes for towing and performance