You can pick up a cable and software off of ebay for $120 I believe I paid. If you were closer, I'd hook it up for you. I'm not sure if I could copy my disk, but I've heard you can find the software online to download, then you get a usb to obd2 cable, and make 3 jumper wires to connect it(I opted for the premade cable because I wanted it to be a clean connection).

Ferm thanks for the offer, I'm not to good with computers I live in nj Northern part, the problem is if I bring it in to a marine mechanic you know it's going to be very expensive, it always is and the issue I'm having is pointing to the TPS

the air control valve controls bypass air when the throttle is closed or near closed.
The computer adjusts the open/closed timing of the valve by looking at the intake air pressure(there is a pressure sensor there) From my experience on my suzuki, your symptoms are exactly what happens when the iac valve isn't working right.

If I were you, I would do the simplest things first...
1- remove the air filter on the valve and see if it gets better
2- spray the crap out of the throttles and the iac valve(remove the hose and really get in there) and see if it gets better.
3- clean the contacts of the plugs on the iac valve and the air pressure sensor

If none of that helps, you need diagnostics. You can't just start replacing things because they will require adjustment. Your best bet is a Yamaha dealer who will find the problem fairly quickly and fix it. You are going to pay for his expertise, his software, his ability to try a part he has laying around... That will probably be cheaper than buying software, a connector, and maybe not the right part(s).

I don't have a Yamaha and I'm not an outboard mechanic but I did stay at a Holiday Inn....
Are there no blinking indicators on your Tach that might be telling you what is wrong?
I was lucky, the Suzuki flashed a code that pointed to the IAC valve timing.
The Service manual($7 download) had an adjustment that could be done without a computer.

Tps can cause surging, but so can any of the other sensors on the engine. Pull a $100 bill out of your wallet, light it on fire, if this doesn't bother you, then by all means start throwing parts at it. If it does bother you in any way, pay the money and have it scanned. Way to many engines become projects and end up sold or parted out because people started guessing saying this part points to it, or that. Seen it happen too many times, and don't like seeing it.

Ferm I understand and agree with you but it seems like every time (2) times I took it in it was a grand And I have to take it to a yammi dealer I don't mind paying just be fair I'm thinking hook it up to a computer part is probably less than 100 a hour putting it in should not be more than 300 But I know it's going to be a lot more I'm not a cheap person but dam

Well, I opened up the wallet and dropped her off today, thanks for all the advice but it came down to just bringing her in,,,,, those dam computers I will let you know what was wrong when I get her back Thanks again guys

I was just told that the air I'd le control valve needed to be adjusted, they said it is not bad just not in adjustment and that should take care of my problem, thanks to all for all the replys You guys are the best

Um, it's not adjusteable if it's anything like the bigger yamahas I've worked on. Most likely it was carboned up, and they cleaned it.

yea, I was going to say the same thing, how ever, theer is a trick used to get them to idle better by resetting the throttle plates to put the IAC in a different range, Ive never had a need to do it, but Ive heard of others doing it. It puts the IAC in the 40-60% range rather than the 80-90% range. That still shouldn't have anything to do with the above idle surging, unless it was sticking open

Still no good, dropped her off at the shop in the water, they will have to duplicate the issue on the water hopefully that will solve the problem