Mazda Repair: 1991 mpv tach signal, air intake hose, air flow meter

Question
Sorry, Original problem, timing belt broke. I replaced it and took it to the shop to have it timed properly. After timing, they said the air flow meter was bad, thus the flooding. Replaced said airflow meter. Now the problem has magically moved to an intermittent tach signal. They say it now randomly loses the signal and runs poorly until shut down. That's how we got from flooding to tach signal. I think perhaps they have ruined some wires in their attempt at diagnosis. Also they had the air intake hose replaced at time of air flow meter replacement. Before the broken timing belt, it was running fine, just not starting in cold weather. Thanks again for your time,   John
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The text above is a follow-up to ...

-----Question-----
I currently have the vehicle in the shop. so far we have thrown money and parts at it. The tech says it is not getting a tach signal intermittently.This is not what it was in for originally.They seem not to know why it does this . I do know that they have had the ecu wires off and on about 5 times trying to fix the original flooding problem.Could they have damaged the wiring harness or introduced the problem? It had not done this before I took it in.
-----Answer-----
not sure why a 'tach signal'  would cause a flooded engine, could you explain in detail what the vehicle was doing before you brought it in to have it fixed

Answer
since it was running ok before t-belt broke, and this is a non-interference engine, i would suspect the cam gear/crank timing is not right, off one tooth on either will  cause all kinds of problems, it's not hard to get them off a tooth either, i use mirrors and still get it wrong sometimes.