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Rpm signal goes to 0


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My car started having random rpm drops out of nowhere. It would loose power and come back over and over. Had to let it sit a minute before I could get it to start again. Did a trigger scope and saw crank position signal noisy and pulled the cover apart to inspect. I found that the hall effect sensor air gap to trigger wheel was not in spec and showed signs of it touching the teeth slightly. Also found some metallic trash arround the wheel. Cleaned it up, remove the trash and set the air gap to spec and did another trigger scope. Signal is much cleaner than before but some waves have random voltage spikes and drops. Would this cause the engine to loose sync or did I have another problem? Using kiggly 12 tooth trigger with 99 eclipse cam position sensor. 20240305_150721.thumb.jpg.e80278c18d8cbb4fbed3b22624ea6740.jpg



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The most likely issue I see is the falling edges of trigger 1 & 2 are only about 3-4deg away from clashing.  This is well within the amount that the cam will bounce around due to belt stretch and harmonics etc.  

The rising edge on trig 2 isn't much better so not point changing to rising, you really need to move the cam edge away from the crank edge by about half a tooth.  Im not sure if the cam sensor is adjustable on that engine like an evo3 or if it is fixed like an evo 4, if it is fixed you could cut the window a little larger in the chopper disc.  Or if you have adjustable cam gears you could retard the cam a few degrees. 

The other issue is the voltage spikes you have on the trigger signal, its hard to say which is the cause of your trigger error but these do appear to be a bit worse than typical.  This would most likely be related to coil wiring, where they are grounded, HT leads, resistor plugs etc.  

I would fix the potentially chasing edges first then look at the electrical only if that doesnt cure it.  


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Thanks, I Slotted the bolt holes to adjust it and the falling edge of triger 2 is now in between falling and rising edges of triger 1. I'll drive it arround tomorrow and hope that was the issue. 

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