The tach working or not shouldn't make a difference.

Have you checked to make SURE the drivers floormat isn't covering the kickdown switch? It slides over and covers the switch, resulting in no kickdown.

Mine stopped working a few years ago and it turned out to be a relay related to the HVAC system. Apparently the kickdown circuit is powered from the AC unit somehow, since the compressor shuts off while in kickdown (to ensure max engine power). It turned out to be the KLIMA relay and it is located between the two firewalls. If you know where the OVP relay is on your car, it's right next to it.

Neal

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