2012 Sea Doo GTI se 155 P2279 but No Leak


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Hello like the title says I have a sea doo gti se 155 with a code P2279. The jetski doesn't rev beyond 3500 RPM and it has some rough idling. I checked everywhere and it all indicates there is an leak in the intake manifold.

Before this happened. I had some electrical issues but I did not have the P2279 code. I took it to a mechanic and he checked everything and cleaned the "throttle body" because the jet ski wasn't accelerating after a week or two he said that the fuse box was corroded (which it was) and that I had to change all the fuses which might cleaned all the other error, I did change every single terminal, cleaned all the wires, and put new fuses. A lot of the errors went away except the P2279 which only happened AFTER he "cleaned" the throttle body.

I did some research and checked everywhere around the intake manifold, there seems to be no leaks, I put my hand all around the intake manifold and felt nothing, I also saw no cracks on it, and just to make sure I bought a new throttle body, cleaned the rubber gasket, and even bought a new gasket, and put some gasket sealant. I tried several ways to put the throttle body properly, but the code never went away.

I also tried disconnecting to MAP sensor(pressure sensor) on the manifold but it gave me an error that the sensor was "disconnected" which makes me think is working.

At this point I don't know what could be wrong with it. I've seen some manifolds for around 250 on ebay. I would like to try to save that money and labor. Does anyone have an idea on what I could do next?

I read online that it could also be a bad MAP sensor(pressure sensor) that is located on the intake manifold. Should I buy a new sensor?
Also would the temperature sensor on the intake manifold cause this error as well?

Just to clarify the jet ski turns on and accelerates to 3500 sometimes upto 3800 RPMs.
Like I said I checked all around the intake manifold and I found no leaks. Is there a way to find a very tiny leak if there's any? Any help would be appreciated thank you.
well I took it to the sae doo dealer and they told me it was the main wire harness causing the error. Some ground somewhere making it mess up. Does any one have any tips and tricks to clean the main wire harness? Should I even attempt it or buy a new one?

What happened is that my jet ski flipped and got a lot of water in it. messed up a lot of things and fuses which I fixed later on and took several errors out I only have 2 active error codes. P1504 and P2279. p2279 is what is giving me the most trouble since it limits my RPM due to a "leak in the manifold" which there's no leak apparently.

If anyone has any experience with this let me know. I'll start cleaning it tomorrow and see if anything gets fixed.
Update: picked up my jet ski from the dealer to try to attempt to clean the main harness.
Tech told me that they tried clearing the codes but the code is active and can't be cleared.

I brought the jet ski home and out of curiosity decided to turn it on. Code P2279 is gone and code P1504 remains (which has something to do with a ground)

Now my jet ski accelerates but I have a problem, it still either has electrical issues or something is up because it idles at aroun 3800-4400 rpms. It doesn't fluctiate as much but the first time it turns on it settles at around 1400-1600 RPMs which is normal, but if I go and accelerate it once, then it stays idling sort of higher every time.

Quick Example:
First time turning on: idles at 1400-1600 rpms or so. If I accelerate jet ski goes up to max rpms like normal but then it idles at 3800-4000
turn off
Second time turning on within the same 5-10 minutes: now idles at 3600-4000 rpms and so on.

After the third time it idles at those RPMS it goes up a little here and there but not so much, let say like 4150 or so.

I'm going to keep updating, I think is going to comedown to cables being corroded and they need cleaning, specially since error P1504 is still active and I still have a check engine light on.

If anyone has any ideas that it might not be the electrical harness please let me know :)
It idles normally between 1700-1800 rpms (I was wrong on my last comment).
-If I slowly accelerate it to 3000-4000 RPMs go back down to normal.
-If I accelerate fast to full throttle lets say 7000+ RPMS then the RPMs get stuck at around 3800-4000rpms and it doesn't come down anymore. I dont leave it on for too long because I don't have to overheat it.

anyone has any ideas why my Sea Doo might get the RPMs stuck so high? I should comment that I have code P1504 but has really nothing to do with the acceleration. Also I should point out that this code was present like a year ago and the jet ski ran without any issues.
1504 is a speed sensor circuit fault, so the ECM is not getting speed info from the speed sensor. Find a wiring diagram for your ski, find that circuit, troubleshoot the circuit.
1504 is a speed sensor circuit fault, so the ECM is not getting speed info from the speed sensor. Find a wiring diagram for your ski, find that circuit, troubleshoot the circuit.
So I realized I got the wrong TOPS switch.
Here's a little scenario hopefully you can help me:
I had to replace the TOPS Valve because I was getting some codes.
- Once I replaced it the codes went away, but I realized the new TOPS Valve does not have the same "slot" for the TOPS switch.
- so I left the TOPS switch loose meaning not attatched to the TOPS Valve (but obviously it's connected to the harness's connector).
-Now the TOPS switch is loose and basically flying around and I get code 1505.
-I thought it was the TOPS switch being messed up, so I naturally bought a new TOPS switch, but I didn't realize I bought the wrong one (even the size of the pins seem different)
-when I connected the new TOPS switch the code 1505 went away and now I get 1504.
- This is when I realized I had gotten the wrong TOPS switch (because of the pins)

What I want to know is: does it matter if the TOPS switch is moving around freely? because my new TOPS Valve (which works) doesn't have the same "slot" to attach the TOPS switch to it.

I asked chatGPT and it looks like it has a tilt sensor. Meaning that I need to attach it properly. Since I don't have the "slot" on my TOPS valve what could be my options? (besides the obvious one of buying ANOTHER TOPS Valve with the same "slot")

to clarify: the "slot" is nothing electric per se is just the way it stays in place fixed onto the jet ski's body/engine/TOPSValve.

Any help would be greatly appreciated.
I think i have the wrong TOPS Valve! because it does not have the "mount/slot" for the TOPS switch.
Just ordered new TOPS valve and new TOPS switch.

Also, I think the reason why my jet ski RPMs get stuck high is because when I put my new throttle body I put some gasket sealant (because I thought I had a leak, which I don't) and that gasket sealant got on the throttle body's "vent" and makes the throttle body stay slightly opened after I rev it up as high as possible.... so is there a way to remove this sealant without having to take the throttle body apart?
The reason why I don't want to remove the throttle body is because when my mechanic did that it threw the code P2279 and it wasn't going away until the dealer reseted my codes... and as you may know the dealer charges like $120 to reset the codes -_-, not only that they think is my harness having rust all over it and they were charging me $1600+ to fix it....

any tips would be greatly appreciate it, thankfully my jet ski "runs" the P1505 code does not affect the "performance" "apparently. So I'm gonna take it to the water for a ride to see if the throttle body gets "unstuck"
I took my jet ski on the water and it was not accelerating properly for a bit. After about 30 minutes of running it works normally it accelerates instantly the RPMs don't get stuck high and it reaches top speed of 56 57 MPH! so basically is fixed!

Now I have to wait for the net TOPS Valve and TOPS switch to see if I can get rid of the code P1505 and see if that gets rid of the check engine as well.

I still have error code P1505 and check engine light on, but the jet ski works flawlessly no issues whatsoever even after running for like 2 hours straight and pushing it as hard as I could. Wish me luck when the new parts arrive.
Last UPDATE***
I got the new TOPS Valve with a new TOPS switch and everything is fixed. The check engine is gone as well as the code P1505. Looks like the dealer does not care about actually diagnosing a jet ski properly. I'm a little affected because if I ever need actual help to fix my jet ski in the future I can't trust these sea doo dealers or techs, they will just do their best to make me spend the most money they can without properly diagnosing the jet ski.
How is it possible that they couldn't figure it out but, I, a complete noob with jet skis was able to find the causes.... I know bassics for cars, motorcycles, etc. This is also my first jet ski ever... I guess is a business and like most businesses they have to fuck over the clients.

One important thing I learned and is super important: NEVER remove any sensors or electrical parts without disconnecting the battery completely. The reason is because, like me, I got the code P2279, which indicated a leak in the manifold, this code seems to be permanent and you will need the dealer to perform a code reset/clear for it to go away. I tried all ways of resetting the codes like disconnecting battery and touching the red and positive cables but nothing... Like I indicated before the dealer cleared the code, but after the clear they didn't turn on the jet ski therefore not realizing that the code went away, all they had to do was run the jet ski not just turning on the display.

Anyways, lesson learned at least where I live I know this dealer wants to squeeze as much money from you as possible.

Things I learned:
1-. Don't disconnect any parts of the jet ski without first disconnecting battery.
2-. cables and electrical stuff are really resistant to water and corrosion even salt water which is what I run only on. EXCEPT fuses! KEEP YOUR FUSE BOX VERY WELL COVERED!.
3-. Sea Doo dealers or dealer in general will fuck you up as much as possible so try to be very specific about your issue and research as much as you can.
4-. If your engine bay takes a lot of water (salt water) just take it out as fast as possible if it got to the fuses CHANGE ALL TERMINALS first then go from there. You can think it messes up everything else but no it could be just fuses which it was my whole problem since the beginning.
5-. If your jet ski doesnt reach max speed, has problem accelerating after you have done a lot of work just run it for an hour in the water. My jet ski was not reaching max rpms and speed even after I fixed a bunch of stuff but it just needed to run for a little now it doesnt have any issues whatsoever.

If i have more stuff that I can share I will do it here.