Idiots...

**** happens.
I wish I had a magic wand to fix every problem and miraculously predict what is going to happen down the road with these old cars.

Sounds like those guys tried to get it right but sometimes without the advantage of a crystal ball, you gotta try stuff until you fix it especially if it's an intermittent problem.

It's nice if we can have the time to drive the cars for a couple days before handing the keys back to the customer but now days everyone is in such a big hurry and they pressure you to fix it right away and think you are supposed to wave a magic wand and miraculously know what is causing the problem.
Sometimes diagnosis is easy and sometimes it goes away for days while you though you fixed it then it acts up on the customer again.
This sucks but such is life.

As a mechanic I understand with my own vehicles that stuff happens but trying to explain that to a bubble gum chewing trust fund brat is another story.