'07 6.0 intermittient start stall issue.. help!
So the problem started last week, after the truck had sat for about 3 hours it started up then stalled after 6 seconds or so. Started it again and only ran for half a second then died. Did this a few more times. Finally started hiccuped, have it throttle and it stayed running. It did throw a code for the crank sensor once. Cleared it and the code never came back. Changed crank and cam sensor anyways since I had new ones as spares. The problem only seemed to happen after the truck has sat for more than 3 hours and it was worse the longer is had sat; however, today is did it after running into the store. Here are some numbers from monitoring with the torque app. Ficm
is always 48.5-49.5. Batteries drop to 11.6-11.8 after shutting down. Voltage while running 13.5-13.8. starter never seems slow to start.
Hot idle: hpop
585 +/- 15 ipr
Cold idle: hpop
650 +/-25 ipr
While cranking with the start stall issue:
400-600 or so ipr
84 (hard to really tell as I think the torque app and obd2 dongle are slow to register).
I did notice a month and a half ago the hfcm relay is missing under the hood but never had any problems. I did notice the problem happened after filling up with fuel. Oil change done 1000 miles ago shell rotella t6 15w-40 motorcraft filter and cap. Fuel filters changed 5000 miles ago. Randomly the oil pressure gauge won't register at idle but I'm getting a code for the oil pressure switch. I think it's just coincidence.
I did an injector a month ago and the dummy plugs and stand pipes looked okay on the passenger side. A little flatness on the o-rings but not bad. Not sure what to check next.