Cam and crank sensor issue on cat motor

He put oil on it ...

 

Is this Pico screen shot an actual C12 crank sensor waveform? Do you recall if this screen shot was taken at idle, or cranking? I may have a similar problem with my C10 3CS002.

 

No it is not actual waveform from C12. The crank sensor uses the crank gear teeth as the pulse wheel. One tooth is partially missing so ECM can pickup TDC on #1. This allows engine to run with only one sensor unlike the older single sensor design. Most issues I have had on the C12 has been rubbing wires close to the oil pan standoff bracket.

 

Thanks for the reply. This truck is on a job-site. Im going to connect a 4 channel digital scope and record cam, crank, injector 1 & 2 to try and get a base line recording for future reference. The best way I found to check for intermittent open/shorted circuits, is to disconnect both ends of the cable (computer and sensor) and Megger test the cable. Yes, the issue is usually near the cable clamp.

 

Cool,just remember injectors are 90 volt. Post your results.

 

Will do!

 

Serious question...

What different crank speed sensors fit a C12/10? apparently the front inner timing covers are basically the same but mine are the crank sensor because it was to long. Cover is stamped 1382008 B 4. I'm waiting for a picture of the one that came off it probably be tomorrow.

 

Did you figure out what was going on? My c13 is doing this for a split second sound like its gonna stall gets to 300 rpms then runs fine