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Engine wont always start


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So it seems sometimes my car wont fire it is like its 180 deg out and can backfire which isnt ideal.i can tell when it doesnt fire now so usually catch it  .if i shut it down  and try again it will fire as per normal although think its usually can be on the 3rd attempt. 

Running a g4+ extreme  

Smart coils, HALL EFFECT CRANKSHAFT SENSOR - HIGH RPM VERSION - H-GTSEN2 via efi hardware and modified dissy for cam sensor  signal

Engine is a hemi 265





pcl file


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That sounds like it isnt syncing on the correct phase occasionally.  Possibly the cam edge either crossing the sync point or its voltage isnt meeting the arming threshold or similar.  Can you do a trigger scope while cranking.  Preferably during whatever conditions causes the slowest cranking speed - on some engines that may be on a cold morning when the battery voltage is lowest, or on some engines it may be for example when its hot and has been sitting a while heat soaking the starter motor.  If you havent noticed any pattern to when it happens most often then just give us a scope done at any time and it may still be useful.  

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sorry i have logged a couple of trigger scopes not sure on what settings to do this .so here goes


https://1drv.ms/u/s!AsueBbAiWzmW11FjduocZjph5xFA?e=ml5qby thanks


this one is the car running






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The first 2 you must have clicked capture before you started cranking the engine so you have just captured the stationary engine.  You need to click capture when the engine is cranking.  

The 3rd scope with the engine running shows the cam sensor is wired backwards.  Swap the +/- wires at the sensor plug to correct this.  I doubt that is causing your start issue though, but fix that first then do us another scope while cranking.  

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