I've just pulled all the MC16 harness off mine and fitted F3 PGM-II stuff, but where I've cut the harnesses about to remove any excess I found some of it was very corroded on both the 87 parts and the 89 parts, even though both looked in good condition on the exterior.
Best thing to do is get the multi-meter out and check each wire for continuity.
If you suspect the tacho itself, then I have an MC16 instrument cluster for sale now!
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Andy.
NSR-WORLD.COM
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