I agree, boating with an engine that has guardian mode without a scan tool or smart craft can be frustrating, diagnosing using a forum and throwing parts at it can be expensive.

Years ago a guy missed a poker run because one of his 700sci wouldn't come off idle, the culprit, a weak impeller making no pressure at idle. Engine was running just as cool as the other.


You also have the option with twins to swap parts, however some sensors are delicate and can be damaged removing them.

If you want a guess, my guess is your TPS. If you have a good volt meter you can back probe and test (google TPS volt meter test)

4bus - Will smartcraft tell you everything that a scan tool will?

Smart craft will read codes and show data stream from every sensor, the smart craft will not perform systems tests such as leak down, base timing hold and other ECU commands.

the smartcraft will not tell you as much info as a scan tool in fact some of the codes thrown in the smartcraft are not correct and need to be checked with scan tool

Smartcraft does not give you the specs nor the parameters of the sensors or for any fault codes. It will show a fault with a abbreviated listing of that fault code on the smartcraft gauge. Example: ESC-NS POS DIFF - means ESC and neutral switch position fault. You have to learn this abbreviations as well as they are in all the diagnostic service manuals thru the OEM's.

Thanks guys, good to know.