zog Posted December 4, 2009 Share Posted December 4, 2009 I have a 2006 f350 6.0l occupying my bay, when cold after sitting overnight it has a long crank time before starting.(cranking the starter for 10 sec, 3 times before starting) no codes. have sync and ficm sync,eot 44 degrees, glowplugs come on, back probed gp relay, power coming out, glow plugs resistance is good across the board. icp@ 1776psi, ipr@ 50% fuel pressure maintains 50-51psi, no combustion gasses in fuel,fuel is clean, oil not aerated. oil filter stock, and not dry after sitting overnight. unplugged icp, ipr rampped to 75%, still no start. latest calibration installed on test ficm. I must be over looking somthing obvious. also notice slightly longer than normal crank time once warm, but not long enough that a customer would complain about. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 4, 2009 Share Posted December 4, 2009 Look at ICPV, not ICP, when diagnosing any 6.0 problems. ICPV should be .17-.24v KOEO and quickly ramp up to about 1.5v cranking. Also I'd look at FICM M_PWR and make sure it's over 47v. GP almost always set codes so I rarely look at those on a 6.0, but if I did it would be with an amp clamp. They should pull 170 amps or so initially, tapering to 120 amps after 30 seconds. What's cranking speed on the scan tool? I use 175rpm minimum cold cranking, as they crank at about 215 warm. If all else checked out I'd look closer at fuel quality or FP return flow to verify good supply. Smell the fuel and let it sit in a glass container in the freezer a few hours for a bullshit test. Good Luck! Quote Link to comment Share on other sites More sharing options...
zog Posted December 4, 2009 Author Share Posted December 4, 2009 Restarted this morning, unfortunetly it is unseasonably warm @42degrees so crank time was just about 2.5 seconds. Icp started at .2v ramped up to 1.3v in approx. 2.5 seconds.Ficm m_pwr stayed steady at 48v. Fuel looked good,smelled good,will try the freezer check this morning. Thanks! Quote Link to comment Share on other sites More sharing options...
iceman Posted December 5, 2009 Share Posted December 5, 2009 i had one with the very same concern seems to have an extended crank time when u get it running drive the hell out of it then do a hpop air test mine was left side blank plug oring starting to eat away it was not leaking enough to cause a no start hot but when it sat over night it would air up and cause a hard start in the morning Quote Link to comment Share on other sites More sharing options...
OHNO60 Posted December 5, 2009 Share Posted December 5, 2009 zog, had same extended cold crank issue on 06 E450 last week. Checked everything,icp,ipr icpv,glow plugs system all within spec,fuel pressure too in spec,swapped ficm with known good, basically all good. Believe it customer stated he would bring it back when it got worse. Well month later came in on the hook for crank no start. Performed diag and ended up being a failed drivres side dummy plug. Replaced both dummy plugs and at same time repaired the extended crank problem. All the readings were all correct and truck didn't have any issues starting after hot engine shutdown soak. Dam dummy plugs caused the extended crank when cold the whole time and didn't even show any of the usual hot restart issues. Quote Link to comment Share on other sites More sharing options...
zog Posted December 7, 2009 Author Share Posted December 7, 2009 customer need truck back, and said he would drop it with us again when it started acting up again. Quote Link to comment Share on other sites More sharing options...
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