I can check it for you in one day, but, I dont think that is your problem. iac drivers can go bad but, the iac never moves when they do.
Mark
504-469-7463

If you don't think it is the computer do you have any other ideas or checks I can do? I looked at my iac at idle and was afraid to adjust it after the book says 0-40 counts and Jim at Arizona speed said my 34 was fine. Any thoughts on a wiring problem? I've tried to visual check all the wiring for shorts or melted wires. I just thought since my alternator burnt up one day then the boat started running bad the next might have something to do with each other.

Thanks for the advice

call me at shop on wednesday
mark 504-469-7463

My 575's would cough upon advancing the throttle w/ IAC set high.
Re-check the manual. It is supposed to be set @ 15.
The only thing that may be different - is yours single or dual IAC? Mine are single.

That's good to know.

One of mine will occasionally sneeze and die when
advancing the throttle off idle....only does it when
cold though....I'll have to check that.

Did you get your alarm problem figured out ?

Mine has 2 IAC's . 1 in each throttle body.

Then your IAC #'s will be different than mine. I am pretty certain your issue is fuel / air related.
I re-read the 1st post and it still sounds like IAC issues - especially the rev up & down.

I got the 575 package from Arizona speed and marine and they have worked great for the last year, great HP for the $

so what did you set the two IAC's up at?
thanks
brian

I have mine set at 10 running at idle. Works well