Abstract: The disclosure describes an improved apparatus and method for displaying and printing the results of an analysis of an internal combustion engine. The results simultaneously are displayed on a cathode ray tube (CRT) face and are written into a buffer memory of a printer. An operator can move a cursor to the line of the CRT display for which special printing is desired. By pushing an ENTER switch, the operator causes a problem flag to be displayed on the screen at the desired line. The information displayed on the CRT face then is printed, together with an additional message indicating a possible vehicle problem. The line designated by the problem flag is printed in a modified ink color to indicate the source of the possible vehicle problem.