Bruce Amacker Posted July 22, 2012 Share Posted July 22, 2012 Helped a buddy out with an interesting one (for me, anyway) on the phone and thought I'd run it by you guys to see if you ever heard of this. '03 F-model 6.0, dies on the road, towed in, no start. Buzz test sounds fine, injector precycle is present, only codes present are VSS, CMP, key switch, some unrelated B codes. I ignore the CMP as IDS shows RPM during cranking and it's probably a ghost code. FP and ICPV are good cranking with ICP going from .23 to 1.9v. I never look at ICP pressure on a no start. I said to put the homemade-dual-lightbulb-injector-harness tool into the injector harness and see if the injectors are being commanded on. I teach this tool in class regularly as it's a great way to separate the engine into two halves- if it blinks during cranking you know the PCM, FICM, ICPV, SYNC etc are happy and your problem lies in FP, injectors, base engine, breathing, fuel quality, etc. I have him check basic electrical such as fuses, CBs, connections in case something weird exists. This guy knows his way around a 6.0 very well and rarely calls me, he stocks most parts including FICMs. He puts the tool in, both bulbs glow during GP for injector warm up, but only one bulb blinks during cranking. He transfers it to several other cylinders with the same result. I told him to change the FICM which fixed it. No injector circuit DTCs, no P0611. He says pre-cycle and buzz sounded normal but I wonder now if it was only one side buzzing, or would it buzz with only one side activated? You might argue the spool would park in one direction and not make any noise. Ever hear of it? Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted July 22, 2012 Share Posted July 22, 2012 It is common for a FICM to show FICM_MPWR above 47 volts KOEO even with the glow plugs energized but drop while cranking the engine. I have seen weird things using my NOID light but never gave it a second thought as like in this case, a new FICM fixes it. I suppose it depends one the "degree" or location of the failure inside the FICM. I agree with you that for spool valves to make noise the valves must be moving in both directions. I had a truck in Friday that made noise when turning the key on but simply would not fire when cranking. In that one FICM_MPWR immediately dropped below 30 volts as soon as I started cranking. I normally don't pull out my NOID stick for a no starts rather more for individual injector circuit failures or dead misfires where normal diagnostics lead to a bad injector as a final test to ensure the FICM is actuating both sides of the spool valve. I have also watched FICM_MPWR voltage vary from 48 to the low 30's and back repeatedly while sitting in the shop idling long after warm up and no glow plug cycling... and still run half decently... and others crank with only marginally low FICM_MPWR and not fire. I have also seen FICM's lose the ability to maintain FICM_MPWR after the engine and the module heat up. Sorry I am throwing a lot of stuff up here but these things come to mind. Quote Link to comment Share on other sites More sharing options...
mchan68 Posted July 22, 2012 Share Posted July 22, 2012 ONE such truck I had a while back comes to mind when reading this. I had what I recall was an early '04 truck (with an '03 engine in it) that would randomly stall out while driving and fail to restart. What was happening while I was monitoring PIDs was it would lose FICM_SYNC out of the blue while driving it, with no rhyme or reason as to what caused it. Like yours, I was getting about 48.5 volts under all conditions, no P02XX injector circuit or P0611 DTCs. What it was getting though, was U0105 (I think???) code though. After checking, and re-checking engine wiring, I swapped in my tester FICM to go for a road test. Sure enough, after the stalling stopped, I slam dunked in a new FICM and it fixed it. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted July 22, 2012 Share Posted July 22, 2012 I have installed reman FICM's that have almost immediately caused the scenario Bruce described. Thankfully I took the time to make up one of them fancy noid light testers. Quote Link to comment Share on other sites More sharing options...
toddt Posted September 10, 2012 Share Posted September 10, 2012 A master tech friend of mine suggested that when you do get circuit code for a injector to first run the injector self test. After you have ran the self test swap the connector for the bad suspect injector for a good one so lets say the number five injector harness move to the number 3 injector and the number 3 injector to the number five. Run the injector self test again. If your original code was for the number five and now after the switch and re-test it is the number 3 then you can rule out the FICM and wiring and it will most likely be the injector that has failed. Quote Link to comment Share on other sites More sharing options...
Buddy_M Posted September 10, 2012 Share Posted September 10, 2012 Normally I have a few cores around, as well as a new injector or 2 always seems to be laying on my box, so I have been known to more than once plug in a new or a known good electrical side core injector to prove out wiring concerns. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted September 10, 2012 Share Posted September 10, 2012 Yes Todd, that will work... if you can get the plugs to reach. Quote Link to comment Share on other sites More sharing options...
joshbuys Posted September 12, 2012 Share Posted September 12, 2012 I made a set of 'jumper wires' specifically for this occasion, use connectors off an old FICM harness and 2 injector cores (ford throws the electrical away when they rebuild them anyway, just make sure they're cores and not warranty) works exceptionally well! Quote Link to comment Share on other sites More sharing options...
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