Engine Revs high when put into neutral.

[Cobber]

Have a 2006 24ssv Gravity Games with the 340 Indmar engine. Our first boat. Second time taking it out the revs started acting funny. When I move the throttle back to neutral the engine would increase revs to about 1300-1500 and stay there. If I press the throttle only button and rev the engine and then back to neutral it returns to normal. Likewise if I turn the engine off and restart it returns to normal. It will do this again and have to repeat process. It doesn't do it all the time but it seems to be happening more often and moreso after running the boat under load. It seems like I need to move the throttle forward quite a bit before the engine engages from neutral, could it be a loose wire or spring? Any ideas what this can be and if I can tackle this myself or do I need to take the boat to a dealer. Just worried if I take it in and not under same conditions they wont see an issue. Thanks for any help.

[garyholl]

It sure sounds like a sticky or loose connection on your throttle linkage. Can you look at where the linkage meets the throttle body and see if anything looks loose? Unfortunately, it's more likely to be a problem in the remote control at the drivers seat and that can be a more difficult situation to identify.

[Cobber]

Yeah I will have to pull the panel off to check the linkage. I haven't used the perfect pass yet so hopefully that isn't playing up and causing it. Mind you my depth qauge just shows 2 dashes so that has an issue too.

[garyholl]

Someone said something about adding some ground wires to the fuse box which I might do. The stereo clicks when I adjust the wake plate and my depth finder shows dashes more than anything. I can't help but think I have a ground problem.

[jzelt]

When mine was doing that, I tried a new IAC (Idle air controller), then switched out the throttle position sensor and have been good ever since. (Few years now). I would start with tps.

[Cobber]

I was searching some other sites and forums and the throttle position sensor keeps popping up. I think I will have a look. Thanks for the reply. Anyone know best place to get one?

This last weekend one of my rear ballast kept filling by itself and then wouldn't empty. Replacing the crappy solenoid not but think will upgrade whole setup next year.

[Zim]

Was going to mention the TPS as well. Doesn't sound like an IAC issue since your boat isn't dying.

[supraaddict]

Mine was doing exactly the same thing, if you take the TPS off it is spring loaded. When I turned my old one with a screw driver it would stick on the idle side of the spring action. replaced mine and she runs good as new. Nice and easy idle at 800 RPM's. Just make sure that when you put the new one on turn the TPS to the left (or towards the front of the boat counterclockwise) to get it onto the small keyed shaft and then turn the TPS to the right to line up the bolt holes (This will load the spring tension). My throttle body had a small plate under it and I simply bent it down to get the TPS on and then bent it back up to flat gently. Very quick, easy and cheap fix. I got my part from Oreilly's and used one off a 1991 K1500 Chevy Blazer. I have the 5.7 Indmar Assault. Hope this helps you out!

[Cobber]

Thanks. That helps a lot. Keep searching for boat parts and forgetting these are basically Chevy engines.

[Cobber]

So I contacted a couple boat indmar parts suppliers and they said for that year The TPS is part of the monovalve assy and the price for that was $289. My TPS has the oval connector and not the round one which most car ones do. This is a pic of mine I think. Was the blazer one like this?
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