Nissan Repair: tach error, stick shift, gears

Question
97 nissan pu stick shift.  about every 3rd time I start and drive the truck the tack will read about 500-700 rpm high in all gears and at idle.  It is a false reading as the engine is not matcching t6he rpm.  What cvan I do to repair a off scale high (sometimes) tach

Answer
John,

You could get a scanner and see if it is getting the correct value from the ignition system.  The computer picks up the value at the cluster and if the code reader reads the correct RPM then you know it is the tach itself.  Either remove and replace with a used unit or take it to a speciality repair place to have it diagnosed and repaired.  I go with the used route to save money.