Give me an ignition system tutorial please.
Thread Starter
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Me too! 
And, I learned-a-thing in the process. I didn't know that polarity mattered on a magnetic p/u. In fact, I was sure that it didn't matter.
While splicing them proper, I asked if he'd noticed orientation before tugging...he told me how he thought they had been connected. I told him that it was a magnetic pickup and probably didn't matter, but we moved forward with the splicing based on his recollection of their orientation. Turns out we were both wrong; He was wrong about the orientation of the two wires....I was wrong that it didn't matter. I still don't know WHY it matters....but apparently, it matters. 
So the original problem that caused the car to die was the bad/failed/hacked butt-connector joint of the crank sensor wires. Our own story-telling f'ed ourselves, and exacerbated a simple problem.
And, I learned-a-thing in the process. I didn't know that polarity mattered on a magnetic p/u. In fact, I was sure that it didn't matter.
The cam and crank sensors were butt-connector'd by the PO. Car's ran great for the past year like that, but then died suddenly. My FIRST thought was those butt connectors, and I had my son tug on the wires...crank sensor wire pulled right apart. "That's it!"
So we spliced them proper, heat shrink'd them...but still no start.
So we spliced them proper, heat shrink'd them...but still no start.
So the original problem that caused the car to die was the bad/failed/hacked butt-connector joint of the crank sensor wires. Our own story-telling f'ed ourselves, and exacerbated a simple problem.
Tech Contributor
Joined: Jun 2004
Posts: 20,942
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Me too!
And, I learned-a-thing in the process. I didn't know that polarity mattered on a magnetic p/u. In fact, I was sure that it didn't matter.
While splicing them proper, I asked if he'd noticed orientation before tugging...he told me how he thought they had been connected. I told him that it was a magnetic pickup and probably didn't matter, but we moved forward with the splicing based on his recollection of their orientation. Turns out we were both wrong; He was wrong about the orientation of the two wires....I was wrong that it didn't matter. I still don't know WHY it matters....but apparently, it matters.
So the original problem that caused the car to die was the bad/failed/hacked butt-connector joint of the crank sensor wires. Our own story-telling f'ed ourselves, and exacerbated a simple problem.
And, I learned-a-thing in the process. I didn't know that polarity mattered on a magnetic p/u. In fact, I was sure that it didn't matter.
While splicing them proper, I asked if he'd noticed orientation before tugging...he told me how he thought they had been connected. I told him that it was a magnetic pickup and probably didn't matter, but we moved forward with the splicing based on his recollection of their orientation. Turns out we were both wrong; He was wrong about the orientation of the two wires....I was wrong that it didn't matter. I still don't know WHY it matters....but apparently, it matters.
So the original problem that caused the car to die was the bad/failed/hacked butt-connector joint of the crank sensor wires. Our own story-telling f'ed ourselves, and exacerbated a simple problem.
Pro
Joined: Dec 2018
Posts: 734
Likes: 424
From: Wisconsin
2023 Corvette of the Year Finalist - Modified
2022 C4 of the Year Winner - Modified
Finalist 2020 C4 of the Year - Modified
Another possibility why the wires being reversed caused a no run: it is possible that is a hall-effect sensor. I've got a few of them in the Holley system in the 85. Normally those sensors are three wire: power (5v or 12v), signal out, and ground. It is possible they are using the sensor body as the ground. If the power and signal out are reversed, there will be no signal output.
