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1999 STS P1350 & P1375

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Hello, everybody.
I bought a 1999 Cadillac Seville STS back in August with 134,000 Miles for $1,800 USD. It was a steal.
For awhile now it's had the P1350 & P1375 codes, no working tach, misfires when cold, and bucks at full throttle. I've replaced both the CKP's, and the ICM. Neither of those were the problem. I'm suspecting that the wiring harness that runs from the ICM to the CKP's has been damaged by the Exhaust Manifold. I've read a couple of posts where this was the cause with fellow '99 STS owners.
Question is, how do you remove the Wiring Loom for the CKP's? From the front of the car, it appears to go into a large loom that feeds into the fuse box, but that doesn't seem right.
Anybody have instructions on how to remove it?


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P1350 Ignition Control System
P1375 IC 24X Reference Circuit High Voltage

My FSM coverage is 1997 Eldorado, Seville and Deville, and 2002-2011 everything, so I don't have a 1999 FSM that would be definitive about model-specific things like the specifics of the wiring harness. If nobody steps up with a 1999 FSM, I will look at the 2002 FSM, which is probably good for this.

You might consider replacing the individual wires that go past the exhaust manifold, and replace the wire ties that are supposed to keep the wires away from the manifold. Be sure and check between the engine and the firewall, too.

Anyone with a 1999 FSM?

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That's probably what ill do. I'm going to rewire the entire loom because I'm willing to bet the Exhaust Manifold melted/damaged the casing around the copper, and they're either touching each other or something else. Or I just have bad luck with ICM's.
I'm pretty sure it'll be the same for any of the Northstar V8's using the ICM/PCM Ignition system (Mounted at the top rear of the engine), and the typical Plug Wire setup with Coilpacks on the ICM. Not this fancy "One massive coilpack that costs more than an arm" stuff.

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