you need to carefully check the wiring to the sensor at WP manifold (the one you replaced I suppose) and look for breakage.
Even though the outside wiring loom may seem fine, there might be broke wire or damaged insulation inside and causing a short which would explain the default strange reading.
Heat and age are big enemy to the wiring.

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2010 BMW M6 * Black Saphire Metallic * Full Black Merino Leather
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