pluguglyinhere

So I have an 06 Nordics Rage with the 496 MagHO with 125 hours. We bought it last year ran great all season no issues. Took it off the trailer a couple weeks ago, idled to the slip, seemed fine first trip out it stumbled, like loaded up under load after idle. If I ease into the throttle in gear off idle it stumbles likes its going to die and gets worse as I add throttle. If I bring it back its fine, seems to be between 1000-2000 and if I ease into it. If I get on it quickly off idle it seems to be fine. It eventually stops stops and runs fine after a while but has done this both times we have been out this year.

It starts, idles fine, even revs fine in neutral quick or slow. Once in gear if we ease into it it stumbles and will not quit no matter throttle position. If we get on it its seems to be fine until we drop back again under 2000 and it starts up again. It has quit both times after a while and runs fine.

We stored it with no fuel as recommended by our shop. I have never done that with other boats was always taught to store with fuel to eliminate air/temp change. I did put premium in, as I did all last year and only mention that because searching posts I saw a lot on not running 91 (premium) and it causing problems. So water in fuel from storing the aluminum tanks empty, bad fuel or ?

pluguglyinhere

What does it act like in "Gaurdian Mode" I think it might be a continous beep gardian mode? I heard a constant beep this time.

Knot 4 Me

Need to scan for codes but sounds like an IAC valve gone bad.

pluguglyinhere

So I may just thrown and IAC at it. Napa calls it an idle speed control, is the napa Echlin brand ok? Should I get it some where else or is that ok. It is fine no beep until I move past 1000 rpm, and only easy, then it start to act funny and beeps constant. I can come back to 1000 and all is fine and if I come back and jump on its fine until I get back between 1000-2000 then it starts again. It eventually stops and is all fine. Is the NAPA one Ok?

pluguglyinhere

So I scanned it and found this

PITOT CKT LO
fUEL LVL CKT HI
STEER CKT HI
FUEL LVL2 CRT HI

These all seem like the ones I ignore because I dont have those sensors.

I started the boat in the water to test the IAC and found these faults also in the history

BLK PSI LO sea water at .04, engine speed 1481, state running, in gear

5 BLK PSI CRT LO seawater pressure was .04
6 NUETRAL OVERSPEED sea pressure .04 same hour
7 BLK PSI CRT HI sea water at 30.39 same hour

all those (5,6,7) were in nuetral no speed, state was stall, and engine speed 0

8 Gaurdian sea water pressure .04
9 OVERSPEED sea water .04

These two show, Engine speed 1490, State Running
These were all at the saem hour on the boat.

I also tested my IAC and according to Rinda the boat needed to be running in nuetral, at operating temp so I did. The test was supposed to generate a change in idle and I got nothing. I ran the test both ways in increments of ten and heard nor saw any changes in the motor running.

Thoughts, what is BLK PSI CRT LO and BLK PSI LO

Keith Atlanta

Plugs?

How rough is is? Mine is a little rough in that zone but always has been....

pluguglyinhere

It idles like normal revs in neutral as normal. We idle in gear fine heading out of the marina get to the end of the no wake and if I ease up past 1000 rpm it stumbles, wont go I have to come back and its fine. I have no idea what Gaurdian mode acts but this is missing or coughing. I can come back to 1000 no problems. I can hammer it off idle and it will scream all the way no issues until I bring it back to between 1000-2000. This has happen three times we have been out, each time we just idled around the lake to our spot, sat for an hour and when we went to come home all is good no problems.

What is the BLK PSI or BLK CRT PSI?
Was my IAC supposed to change something during the test? (the boat nor computer did anything, I just kept doing what they said)
I had a brand new sea water housing and impeller last year. But it acts to me (if BLK PSI is sea water pressure) it doesnt get good flow, so goes into gaurdian but after idling around it works it out and is fine. Is there a valve or something during un-winterizing they might have missed?

Sydwayz

iTrader: (1)

Do you have a water pressure gauge? What does the live data on the Rinda say the water pressure is? Does it go up with RPM?

I think you have a couple problems here.
The stumble could be the IAC, going bad, but not shot yet (or throwing codes). You can't go wrong with buying an IAC. You will need it eventually anyhow.

When you stored it with no fuel in the tank(s), did you be sure to run Stabil through the system as you were winterizing? Do you have ethanol fuel in there? Was it treated?
I would also look to measure the fuel pressure. There is a port on the top of the engine that you can do so with.

Untreated ethanol fuel will ruin your fuel pumps. I know that from experience.
Also, did you put on a new fuel/water separator for the start of the season?

BUP

iTrader: (9)

2006 model year was the start for the Gen III cool fuel system if you have this app there will not be a spin on water fuel sep filter. I will say it again and again up here, all marine engines go off of engine serial # to determine what set up you exactly have.

Year of the hull means nothing to a person who works on OEM marine engines professionally. OEM marine engines relates to serial #'s for the correct apps and correct parts ordering / installed along with set ups.

If you have the Gen III cool fuel system, there is 2 fuel filters in that assembly. The bottom pad fuel filter is this motors most important filter. It is a round disc pad fuel filter of 10 microns with a small mesh screen for support. It easily can cause a fuel restriction. We see this filter not change a lot causing fuel restrictions. Also make sure the inside of the fuel cell is clean from paint peeling, debrie, and corrosion. Yes Mercruiser has paint that peels off inside the Gen III cool fuel cell causing fuel restrictions as well.

So for a cheap POSSIBLE fix change those 2 filters and install a new oring for the top lid of the Gen III cool fuel cell. Also there is a basket in that cell as it can collect water ( that's what it supposed to do if there is any form of water in the fuel). Dump it in a clear jar to see if you have any water in your fuel.

Another test, run your motor on a remote gas tank with fresh fuel like a remote 3 to 6 gallon as what a small outboard motor would use. This helps a couple of things - one is fresh gas and a clean gas tank from a known source and it can tell you which side your problems are, meaning motor side or a fuel delivery side to the motor.

if you reach full throttle and full rpms your motor is not reducing power or in any from of guardian mode period. A fuel pressure test would be a check here as well thu out your rpm range.

BUP

iTrader: (9)

Oh forgot - BLK PSI CKT LO means Sea pump pressure circuit low. which can mean block pressure sensor circuit is open = wiring problem or a sensor problem

BLK PSI LO means sea pump pressure is low. Now this could cause Guardian depending on temp of the motor internally. IMO you might need a new water pressure sensor if in fact you are showing these codes. Also new ones right out the box have been bad so a heads up on that issue if you are replacing them.

I also agree about the spark plugs especially for the 496.