robp823 Posted November 7, 2014 Share Posted November 7, 2014 I keep getting codes for for cmp and ckp incorrect signal signature.Ive load tested both circuits and checked for shorts.Everything checks out fine.Ive tried a cmp sensor,ckp sensor, and a test ECM.It still will not fire.I did notice when I pulled the cmp sensor out it had metal shavings all over it.So I scoped out the sensor bore.I can see the timing peg on the cam and don't see any damage.Is it possible that one of the gears slipped out of time??? That's where im at.Any help appreciated. Quote Link to comment Share on other sites More sharing options...
tonybullitt Posted November 7, 2014 Share Posted November 7, 2014 I haven't done on a lcf but on a 6.0 I use the diesel cam timing guide and scope the crank and cam signals. diesel_cam_timing_2.pdf 1 Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 7, 2014 Share Posted November 7, 2014 By the way were there any codes and what were they? Metal shavings are never a good sign. Also, this is a crank no start? Does it sound like it WANTS to start? Do any codes REPEAT? I ask this because, like a 6.0L a 4.5L can set cam and crank sensor circuit codes due to low RPM misfires and hard starting concerns. That would make the codes a RESULT of the concern rather than the CAUSE. Just something to think about and consider. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted November 7, 2014 Share Posted November 7, 2014 I remember replacing quite a few engine harnesses on LCFs with the encapsulated harness for CMP/CKP issues. Mind you, I've never seen one with metal on the CMP sensor. Quote Link to comment Share on other sites More sharing options...
robp823 Posted November 7, 2014 Author Share Posted November 7, 2014 Cranks fine.Have battery charger hooked up.After about 3 seconds of cranking the faults set.It does not sound like it wants to fire. Quote Link to comment Share on other sites More sharing options...
robp823 Posted November 7, 2014 Author Share Posted November 7, 2014 Fault codes 143 and 147. Quote Link to comment Share on other sites More sharing options...
Revitup6k Posted November 11, 2014 Share Posted November 11, 2014 I had a 6.0L with identical symptoms a while back, I checked the cmp and ckp circuits like you have, replaced the sensors, I was stumped. Then I learned that the PCM relays the signals to the FICM, I found my short between the PCM and FICM. Just a thought. Quote Link to comment Share on other sites More sharing options...
tonybullitt Posted November 20, 2014 Share Posted November 20, 2014 robp823 Did you figure it out? Quote Link to comment Share on other sites More sharing options...
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