Hi, I could really use some veteran/expert advice on this issues I've been having with my 2006 Seadoo GTI SE. I just bought this PWC about 3 weeks ago but it's had this problem since the first ride I took with it. It has 90 hours on it and the previous owner hadn't used it in 2 years prior to selling.
The Issue:
The jet ski runs great for about the first 30-45 minutes that it's on the water. Full rpm range, speeds up to 56mph, super responsive throttle, etc. But after about 30 minutes of use (and rather light use if I'm being honest like 1/2 to 3/4 throttle most of the time) it will become less responsive to throttle input until the only thing it can do is idle at approx. 1700 rpms. After this point, any application of throttle with either: do nothing, or cause the jet ski to sputter and stall. There are no alarms, no check engine lights, nothing. If I keep it off for 5-10 minutes it will run perfectly fine for a few minutes and then go back to only idling shortly after.
The Attempted Fixes (so far):
I scoured the forums and used my own experiences from working on boats for the past decade to diagnose and try to solve the problem. My first thought was bad gas, given that it was not used for over 2 years. So I fully emptied the tank and refilled with new gas. It solved nothing, although the prior gas was definitely bad. My next thought was maybe the fuel pump was overheating or failing while being used. So I pulled the fuel pump assembly and changed the fuel pump and both fuel filters. Still no dice. I also swapped the sparkplugs for new ones at the manual's specified gap of .030 as well as check all the fuel injectors to make certain they weren't clogged or dirty. The issue is still present. I read that it could be the idle bypass valve or the TPS. I checked both with a multimeter and they both appear perfectly functional. I also checked every single fuse, all were good. I'm at a bit of a loss of ideas now...
Current thoughts:
With zero warning lights coming on the dash, it's really hard to pinpoint what could be causing this. The jet ski 100% acts as if it's in limp home mode after it gets warm but without any dummy lights. I ran it on the hose earlier today and let it run for about 20-30 minutes until the pitch of the engine changed and it was slightly less responsive to throttle input. The head and the exhaust water hose felt HOT but from what I've read, the OEM thermostat opens at 188°F which is much hotter than the standard 140-160°F that most boat engines operate at and I'm used to. The water that comes out of the exhaust is also hot but if I could guess it's probably nearer to 200°F. I've already ordered a 160°F thermostat to replace the OEM one, but I have my doubts on that being my solution. My next idea would be to see if I can get a dealer to read the ECU and see if there are stored codes.
Has anyone else experienced this behavior out of their 4 tec engine or have other ideas of what might be causing it to act this way?
The Issue:
The jet ski runs great for about the first 30-45 minutes that it's on the water. Full rpm range, speeds up to 56mph, super responsive throttle, etc. But after about 30 minutes of use (and rather light use if I'm being honest like 1/2 to 3/4 throttle most of the time) it will become less responsive to throttle input until the only thing it can do is idle at approx. 1700 rpms. After this point, any application of throttle with either: do nothing, or cause the jet ski to sputter and stall. There are no alarms, no check engine lights, nothing. If I keep it off for 5-10 minutes it will run perfectly fine for a few minutes and then go back to only idling shortly after.
The Attempted Fixes (so far):
I scoured the forums and used my own experiences from working on boats for the past decade to diagnose and try to solve the problem. My first thought was bad gas, given that it was not used for over 2 years. So I fully emptied the tank and refilled with new gas. It solved nothing, although the prior gas was definitely bad. My next thought was maybe the fuel pump was overheating or failing while being used. So I pulled the fuel pump assembly and changed the fuel pump and both fuel filters. Still no dice. I also swapped the sparkplugs for new ones at the manual's specified gap of .030 as well as check all the fuel injectors to make certain they weren't clogged or dirty. The issue is still present. I read that it could be the idle bypass valve or the TPS. I checked both with a multimeter and they both appear perfectly functional. I also checked every single fuse, all were good. I'm at a bit of a loss of ideas now...
Current thoughts:
With zero warning lights coming on the dash, it's really hard to pinpoint what could be causing this. The jet ski 100% acts as if it's in limp home mode after it gets warm but without any dummy lights. I ran it on the hose earlier today and let it run for about 20-30 minutes until the pitch of the engine changed and it was slightly less responsive to throttle input. The head and the exhaust water hose felt HOT but from what I've read, the OEM thermostat opens at 188°F which is much hotter than the standard 140-160°F that most boat engines operate at and I'm used to. The water that comes out of the exhaust is also hot but if I could guess it's probably nearer to 200°F. I've already ordered a 160°F thermostat to replace the OEM one, but I have my doubts on that being my solution. My next idea would be to see if I can get a dealer to read the ECU and see if there are stored codes.
Has anyone else experienced this behavior out of their 4 tec engine or have other ideas of what might be causing it to act this way?
