help 2013 mule 4010 gas

[thisisme]

Good day I am helping my grandfather with his mule. He had it in a river and it has not worked right since.

-first we drained all the fulids and replaced with new.

-disconnected all connectors and cleaned and dried

-once we got everything dried out we got it running but very rough

- a friend has a similar model so we tried a few sensors, switched cpu and in the end found out that the throttle body was giving use problem and after talking to the dealer they said that it had to be replaced

- we replaced the throttle body and now we have a different issue

to start we have to give it a little gas(just touch the gas peddle) but

once started it idles very high and stays high, if we give it more gas it loses all power but continues to run.

have tried to adjust the idle but stalls as soon as you lower the idle

it is idling too high to shift into gear as well

pulled off the fuel line and the pump seems to be pushing lots of fuel so i don't think it is the pump( but i have not ruled it out completely)

I have been given a few ideas such as

-the air temp sensor( not to sure about that but if i short out the connector this should bypass the sensor right?)

-I have been told to test the injectors ( what pattern should i look for I am thinking circular but want to confirm)

-I have been told to re-seat the valves( not sure how this would cause it to idle high)

any help is much appreciated thank you