Jesus... why can nobody give a simple answer?
The ignitor is in the distributor. It is the small brown/beige rectangle with 3 plugs on it that are covered with sheaths that look like jelly. Pop off those plugs, unscrew the two screws holding the ignitor in, and replace it with a good one. replace the wires, and you're done. The ignitor is the cause of an erratic tachometer 99% of the time. If that doesn't fix it, then either the replacement ignitor is faulty, your wiring is damaged, or your gauge cluster is faulty.
The ignitor is in the distributor. It is the small brown/beige rectangle with 3 plugs on it that are covered with sheaths that look like jelly. Pop off those plugs, unscrew the two screws holding the ignitor in, and replace it with a good one. replace the wires, and you're done. The ignitor is the cause of an erratic tachometer 99% of the time. If that doesn't fix it, then either the replacement ignitor is faulty, your wiring is damaged, or your gauge cluster is faulty.

RIP 4/23/12
...lets not forget, the 88" Z31 turbo, are my dailys 


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