weird, I've got a 1998 and 2000 vintage Mercury and Pegasus (180 / 280) and they both show Max RPM set when the motor reaches the required parameter.
It's pretty rare but sometimes a weak fuel pump can be the culprit and although ''running them in'' doesn't always works, it does alleviate one source of the potential problems prior to boxing up the engine and sending it in for a check up.
I like the data box you built Dr Honda, nice work
You know............ I just thought of something..... Even though, there isn't any output code for "Max RPM" from the ECU. On my box... once "MAX" is set... I do get a MAX RPM voltage on my box. I guess I could add the code, internal of the box, so once it sees that voltage is set... it displays... "Ready for launch." (lol)
Even though, the data terminal isn't needed... it's nice to monitor the idle, and MAX pump voltages. If they start to drift... you know there is a problem starting. I wish Gasper would add that to his code. (for my Wren, and JC)