cm870 crank no start

[Rawze]

CM870 and 871 ecm's are notorious for going bad after they get more than 8+ years old from vibration, or someone neglects changed the crank shaft damper at 500k mile intervals (or 8+ years). Smacking one with the handle a screw driver nice and hard in certain areas makes them cut in and out when they start going bad.


Also, I have seen plenty of fuel shutoff solenoids go bad even though they are getting power to the coil. if you suspect the fuel shutoff solenoid, simply remove its guts and re-install it to see if that is holding it back.

The ecm will not fire the cylinders during cranking unless it has more than 50 psi+ of fuel pressure too. Anyone checked the fuel pressure while cranking?.