truck (04 excursion, 2WD, early build 6.0, 160k) started missing and rough idle on way home from work after sitting all day in rain - parked. started fine in morning and drove to work with no trouble - it was raining over night too.


to get you up to speed. for a few weeks before had intermittent trouble starting. would fire up as normal, fast and loud, but then stall immediately (usually after sitting overnight). would start back up but with a little long on the key and some gas pedal action. only happen one out of ten or twenty starts and seemed to follow getting fuel in unknown locations while on a trip out of town. decided to change out fuel filters and drain separator. seemed to fix it for a week or so then it happened again two days before above event, while weather was dry.
not sure if related but only recent problem to speak of.


back to current:
- no check engine light or codes (I have a scanner)
- stalled out close enough to home the night in question I rolled it into driveway and tried to start it while rolling in neutral - no start
- once parked in driveway also no start
- next evening wanted to get it into garage (to dry off) and it started but rough idle and missing. this was after 24 more hours sitting in rain.
- been in garage 24 more hours and this evening got it to run but same result (rough idle and hard start). tried to check connections (mainly FICM) and move wire loom around - still same.......


anyone have an idea where to check next, need some diagnostic help!

 

You have any way to get live data. ICP during cranking, you try unplugging the sensor. It's under the turbo, if it is making 500psi or more she should fire. Check the plug and sensor, if it's plug is oil soaked, replace both.

You could try parking nose down, that may prevent oil from draining back... may help the long cranking.

Also, have you done fuel or oil filters? Make sure they are the correct OEM caps and filters, they are inserted correctly and not deformed.

These are known to have HPOP failure, why you really need a scan gauge or torque pro, Forscan..... to read the live data. Guessing isn't a good trouble shooting tool.

 

had to limp it home once with a bad injector, feels the same now when driving - rough idle, shudders when in high gear. had a MIL then but not now.


had to be towed home once years ago and the fix seemed to be going thru and pushing on the wire loom with a piece of dowel wood. thinking that might have resurfaced...... rain? / moisture?


no codes to help the diagnostic start up. not guessing just looking for suggestions. no live data but I've fixed a lot of problems with out it using this site since 2008.


ICP and pigtail dry, no oil visible or leaking. usually parked level at work and home

 

Randy is right with no way to monitor live data it's going to be a crap shoot, how did you test for DTCs? Even if the light is not on it can still store a code , are you getting any water in the cab via windshield drivers side? Also take a look at some ficm connections and ficm relay , other than that need sensor values.

 

What scanner do you have? You could have a cylinder contribution issues, and many scanners would not capture it. My first suspicion is a weak injector. Get a power balance test.