Replaced my starter, now no throttle control and idles weak in spurts

[Majr808]

I feel like I'm just stuck in a rut with my boat this past month. Once I fix something, something else is going out.

As the title reads, my starter recently went bad on my 2005 22v.I replaced it and and my boat starts up very strong now. However, very coincidentally I have no throttle control now. Before the starter went bad a few days ago everything was just fine with the throttle. I put the boat on water today and I can put the boat into reverse or forward, but cannot make the engine rev at all. It's as if my throttle is completely non responsive. I tried pushing the clutch button to throttle it in neutral and it makes no difference.

While the starter was bad I also rewired my anchor light and this required me to get behind the throttle arm to move some wires, but I really don't think I messed any up back there. Inspection all looks how it was.

I also notice that the boat is idling very weak in spurts. It will be ok for 10-15 seconds, and then putter very low but not completely die. This has never happened before, nor has the throttle issue. I imagine they are related?

My shifter is controlled by a cable and my throttle is controlled electronically I believe. I checked the wires into the throttle (Potentiometer?) and they all look good.. I followed the throttle wires back to the ECM and everything looks ok from what I can tell.

The only thing that makes sense to me is that something got bumped or hit when I was messing with diagnosing the starter issue and trying to fix it.

Any help is very very much appreciated. I just really want to get out of this rut and enjoy summer.

[Majr808]

Right when my starter broke I put a few gallons of gas in the tank on the water and I saw a small amount of water spill into the gas tank (maybe 1/4 cup or so). I'm sure this could be causing the engine to be idling poorly... is there a sensor on the engine that could be sensing this and thus not letting my throttle engage?

I put two bottles of Iso Heet in the tank to remove any water that did spill into the gas tank, and I will run that through. Hopefully if water in the tank is causing this problem, that fixes it.

[chpthril]

Id love to see a pick of the throttle body. I dont recall MP having DBW in 05. Was released in 06, but IIRC, it was used on the Ve and V finished out with old school cable driven throttle.

I know that an unplugged knock sensor can cause a limp mode on an 05. Did the KS get bumped off while swapping the starter?

[Majr808]

Id love to see a pick of the throttle body. I dont recall MP having DBW in 05. Was released in 06, but IIRC, it was used on the Ve and V finished out with old school cable driven throttle.

I know that an unplugged knock sensor can cause a limp mode on an 05. Did the KS get bumped off while swapping the starter?

Yes sir, here are photos of the throttle body with the electric sensor (potentiometer I think?)

Where is the knock sensor located / what does it look like? I will check it right now. I have a fake a lake setup at my house.

Photos won't let me upload so I used Imgur.

https://imgur.com/a/qI8gQen

I really appreciate your help on this, I'm pretty stuck unless this Iso Heet works.

[Majr808]

Green cover on throttle wires was only removed so I could inspect the wires, they are all in good shape.

[chpthril]

Thats a pic the shifter/throttle lever. Do you have one of the throttle body, which is on the engine? An 05 with DBW would be a unicorn. If it is DBW, knocking the POT on the throttle lever could certainly cause limp mode.

[Majr808]

I believe this is it.

[chpthril]

Yep, that a throttle motor for sure.

[Majr808]

5.7 340hp marine power engine by the way. I forgot to specify

[Majr808]

Some white smoke coming out of the exhaust when the engine idles weak. Not sure if this is normal.

[Majr808]

Id love to see a pick of the throttle body. I dont recall MP having DBW in 05. Was released in 06, but IIRC, it was used on the Ve and V finished out with old school cable driven throttle.

I know that an unplugged knock sensor can cause a limp mode on an 05. Did the KS get bumped off while swapping the starter?

in regards to the knock sensor... I found it on the starboard side near the bottom of the engine. There’s no way I would’ve touched it while messing with the starter. It’s on the opposite side far from where I worked or inspected.

[Majr808]

Update... I ran the engine for about an hour on the water at idle with 2 bottles of Iso Heet in the tank to clear it out. Sounds better I think but still in limp and not perfect. I was really thinking water in the fuel could be causing this.. the engine sounds like water is in the fuel line.. kind of gasping every so often. So I took off the exit fuel hose from the lower pressure pump and let the motor pump some fuel out into a jar. The low pressure pump definitely works well, but the gas looks clean. No water at all. Maybe the tank is already clear and if there is water it's now in the high pressure pump/fuel rail.

I ordered a heavy duty cylinder wrench and replacement fuel filter to open up the fuel/water separator in the high pressure pump and see how it looks/replace the filter while I'm there.

I also read about potentiometers causing this issue so I ordered a replacement potentiometer and will install it when it arrives.

Tige dealer in my area is backed up on service so I'm on my own for now.

[Majr808]

All fixed. Turned out to be the 12V pink wire going into the TAC module... it got snapped behind the helm where it was connected to the ignition. Once I fixed this, everything came back to normal. Now for the squealing in my engine when I start her up..