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KimH
06-05-2017, 10:09 AM
I have a 2004 Moomba Outback with the Indmar Assault and when it is idling in neutral the rpms are way too high-up in the 1200-1600 range. It is always worse after the boat has been ran at faster speeds (pulling tubers vs wakesurfing). Has anyone had this issue? Any suggestions as to what could be causing this? TIA

Stazi
06-05-2017, 10:28 AM
Is it the carb version? Idle air speed may need adjusting or the throttle body could be gummy and sticking open, and might need to be cleaned


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mmandley
06-05-2017, 12:34 PM
You might also look at any vacuum hoses. Bad hoses will cause high idle

Mikes
06-05-2017, 01:24 PM
Does this happen everytime its in neutral or random?

KimH
06-05-2017, 02:50 PM
Mine is fuel-injected.

KimH
06-05-2017, 02:55 PM
It happens about 80% of the time. It's okay for the first little while but the lowest
it will go is around 1000 rpms at rest after it has been running for a little while. Yesterday it was between 1400-1600 after I had been pulling the tube.

sivs1
06-05-2017, 02:58 PM
Simple solution, stop pulling tubes!

KimH
06-05-2017, 02:58 PM
It is fuel-injected. I sprayed the throttle body with Wd40 so I'll see if that helps cleans things up.

KimH
06-05-2017, 03:00 PM
Haha. The kids wouldn't be too happy with me.

lee
06-05-2017, 07:45 PM
Could be an IAC valve.

Stazi
06-05-2017, 09:14 PM
Could be an IAC valve.

True.


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Mikes
06-06-2017, 03:22 PM
We chased the same problem for over a season. A new tps and its plug fixed it completely.

mmandley
06-07-2017, 07:40 AM
You might still have a vacuum leak, you can spray WD 40, but I would use Carb cleaner as its not a lubricant, praying lubricants into the intake can cause gumming, fouled plugs.

Spray around the intake manifold gasket, the throttle body mount, anything bolted to the intake. While the engine is running, if you hear it bog down then that's your leaking area.

It sounds like the engine is getting hot and then your having some leaking issues.

The TPS could very well be an issue but something like that should be reading badly anytime your high throttle then goto Idle. Since that seems to be when your noticing this problem the most.

Zoch
05-26-2018, 07:43 AM
You might also look at any vacuum hoses. Bad hoses will cause high idle

I have a similar problem. I own a 2017 Moomba mondo surf edition, just put it in, won’t idle below 1500 rpm, just had the wiring harness replaced this past winter. Dealer told me computer needs to be replaced, any other options before I trailer my boat 2 hours back to the dealer and ruin my Memorial Day weekend?:mad:

Stazi
05-26-2018, 07:49 AM
I have a similar problem. I own a 2017 Moomba mondo surf edition, just put it in, won’t idle below 1500 rpm, just had the wiring harness replaced this past winter. Dealer told me computer needs to be replaced, any other options before I trailer my boat 2 hours back to the dealer and ruin my Memorial Day weekend?:mad:

Oh that sucks. Bad harness on a new boat? What is the reason for the replacement and why would the ECM need to be replaced as well? How did all that come about?


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Zoch
05-26-2018, 07:59 AM
Never had a problem with it last summer, when I took it in to winterize it, dealer said they couldn't start it and they replaced the wiring harness. Dealer is telling me over the phone that it is the computer, I tried disconnecting all power and resetting, hasn't worked. Any ideas on how to fix before I trailer it back?

Stazi
05-26-2018, 06:46 PM
Never had a problem with it last summer, when I took it in to winterize it, dealer said they couldn't start it and they replaced the wiring harness. Dealer is telling me over the phone that it is the computer, I tried disconnecting all power and resetting, hasn't worked. Any ideas on how to fix before I trailer it back?

Sorry. Wish I could help, but sounds like something beyond a simple fix.


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Edo88
05-26-2018, 11:31 PM
You can usually do a capacitive discharge on computers and do a reset. Disconnect the batteries and touch the ground and positive cable together this will clear the capacitors in a module make 100% sure though batteries are disconnected other wise you’ll make some sparks and potentially mess up some other stuff


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Zoch
05-31-2018, 03:07 PM
Just following up on this issue, there was a vacuum hose disconnected, rpms dropped once we reconnected it and it ran fine for a while. Now I am getting the following diagnostic message: DTC 1157: Closed-loop gasoline bank2 high
SPN: 4238 FMI: 0 ADDRESS: 0 PLUG ID: B

Any help on this? Thanks in advance!

Stazi
05-31-2018, 03:53 PM
Just following up on this issue, there was a vacuum hose disconnected, rpms dropped once we reconnected it and it ran fine for a while. Now I am getting the following diagnostic message: DTC 1157: Closed-loop gasoline bank2 high
SPN: 4238 FMI: 0 ADDRESS: 0 PLUG ID: B

Any help on this? Thanks in advance!

Unhook the battery and let the ECU reset. It is probably all confused now after compensating for the vacuum leak which you then corrected.


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mmandley
05-31-2018, 07:10 PM
Correct I would do the ECU reset again.
DTC 1157: Closed-loop gasoline bank2 high

Was the vac hose on that side of the engine? because with a Vac leak the engine runs Lean so to compensate it adds more fuel to that side. The Engine isn't direct Inject so it will cause the injectors to spray fuel for a Longer period of time.

After you found the hose disconnected it doesn't realize this and still running those injectors rich.

Unlike Cars, Boat have come a long way with computers but they still don't have no where near the sensors, this is a really good thing, so unlike a car when you fix a simple problem like a leaking Hose, it won' know that.

It compensated for the Lean factor but doesn't know how to compensate the Rich Factor. This could also lead to or show you have an O2 sensor acting up, because the O2 sensor is hat helps control the Fuel mixture in the engine.