Mitsubishi Repair: 1992 Diamante Engine Misfiring, hesitation problem, angle sensor

Question
Had spark plugs changed and I noticed the the Tachometer wasn't moving when driving. Recently had right front axle and front brakes and rotors done. Then when driving, car started to hesitate and lose power.
Took it AAMCO and had a diagnostics done and was told that couldn't get a reading because my check engine light isn't on and a more advanced diagnostics would be necessary. But mechanic did state that the engine is misfiring and the Tach isn't working. What should I do about this problem?

Answer
Charles,
I'm not quite sure, but I believe the tach on that vehicle is tied into the cam angle sensor.  If that sensor was disturbed in some way when the spark plugs were changed, it cause the tachometer to stop moving.  The spark plugs and ignition coil should be examined to make sure they are both working properly.  If the new plugs were installed improperly, that may have caused our hesitation problem.  Have the mechanic that installed your plugs examine the ignition system again, or find another mechanic.
Good luck!