Aguyindallas
New Member
Hey all...I have a rough guess that I have a bad IAC on my port engine. It will no longer idle. Here is the sequence of events this season that leads me this way...its a long one, so bear with me.
About 2 months ago, we moved from one marina to another, on the same lake. In that process, we loaded all of our dock items (dock box, trash can, patio furniture etc) onto the boat and took a slow cruise across the lake. I never got above about 1300rpm. It took about 45 minutes to make this slow trek. No big deal. When I was about to back into my new slip, the port engine died. I put it back in neutral and started it. It idled, but as soon as I shifted into reverse, it stalled. This happened 3 times. Then....it went back to normal, no issue. I got in the slip, ran it a little bit longer, no issues.
Fast forward a month and I change my oil (run it at idle in the slip for a while, no issue.) Fast forward another 2 weeks and I change the impellers. Ran both engines and no issue EXCEPT at random, the Port Side engine started to idle about 100rpm higher than the starboard. I revved it a few times and it still went back to the high idle. I turned both off, turned off the ignitions inside the cabin and tried it over again. Engine started right up and idled at normal range in line with the starboard engine.
Now....yesterday....I start the engines to run them a bit before we head out. The port side ran for about 15 mins at idle and died. When I go back to restart it, it will start right up but immediately stalls. No change to even get it to throttle up to try to get a little rev and see if its stumbling etc. So, retart, die, restart, die, restart, die....then eventually after 7-8 attempts, it started to crank but wouldnt start (almost as if it were a carb engine that is flooded). Then it would go back to the restart and immediately die. I gave up and went home.
My initial thought is bad IAC, but I really have no idea. The boat is a 2004 320DA with 496Mag, stern drive. How can I diagnose this without just throwing parts at it? Any tips??
About 2 months ago, we moved from one marina to another, on the same lake. In that process, we loaded all of our dock items (dock box, trash can, patio furniture etc) onto the boat and took a slow cruise across the lake. I never got above about 1300rpm. It took about 45 minutes to make this slow trek. No big deal. When I was about to back into my new slip, the port engine died. I put it back in neutral and started it. It idled, but as soon as I shifted into reverse, it stalled. This happened 3 times. Then....it went back to normal, no issue. I got in the slip, ran it a little bit longer, no issues.
Fast forward a month and I change my oil (run it at idle in the slip for a while, no issue.) Fast forward another 2 weeks and I change the impellers. Ran both engines and no issue EXCEPT at random, the Port Side engine started to idle about 100rpm higher than the starboard. I revved it a few times and it still went back to the high idle. I turned both off, turned off the ignitions inside the cabin and tried it over again. Engine started right up and idled at normal range in line with the starboard engine.
Now....yesterday....I start the engines to run them a bit before we head out. The port side ran for about 15 mins at idle and died. When I go back to restart it, it will start right up but immediately stalls. No change to even get it to throttle up to try to get a little rev and see if its stumbling etc. So, retart, die, restart, die, restart, die....then eventually after 7-8 attempts, it started to crank but wouldnt start (almost as if it were a carb engine that is flooded). Then it would go back to the restart and immediately die. I gave up and went home.
My initial thought is bad IAC, but I really have no idea. The boat is a 2004 320DA with 496Mag, stern drive. How can I diagnose this without just throwing parts at it? Any tips??
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