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The crank sensor on your Wrangler goes down into the bellhousing of the transmission. Slide underneath and look up toward the top of the bellhousing on the left side. At about the 11:00 position you'll see a sensor that goes down into the bellhousing, held in with either one or two small bolts. This is the crank sensor. It's wiring goes up into the engine compartment, where you'll find the connector either at the end of the fuel rail or at the rear of the engine block on the right side.