“There is a device that you can borrow from a car part place. (like Auto Zone or Checkers), that you can plug in and find out what the problem is. Unless you live in California. In California you have to pay a mechanic to do it. Another reason why I don’t live in that state anymore.”
And that is why I now own a scan tool. Only trouble is, with the particular OBDII vehicle I have (’02 Mercedes E-class) it doesn’t do the manufacturer-specific codes.
I have a 1994 Olds Cutlass. Runs great - 110,000 miles. If I go over 50, the “Service engine soon” light comes on. Had it checked - no one knows why that happens.