Jet Ski Won’t Take Off Or Accelerate

If this sounds like your jet ski…

  • Slow take off.
  • Shuts off during taking off.
  • Sluggish.
  • Vibrates like crazy when taking off.
  • Not getting to the speeds it used to.

Then we have some ideas as to what could be the problem below.

Sucked Something Up

One of the most common things for a jet ski not wanting to take off is from sucking something up. Sucking up things into your jet ski can lead to cavitation. You might not even realize you sucked something up most of the time, as the engine is so powerful that it will blow the debris right out of the pump without skipping a beat. 

Other times you’ll notice you’ll suck something up by the sound it makes, or the craft shakes violently. If the jet ski is shaking when you’re trying to take off or just lacks power at take-off, then it’s a good chance you sucked something up.

If you’re on a Sea-Doo, you’ll damage the wear ring as it cuts a groove into it. If you want to learn more about the wear ring, I have a post on it here.

A jet ski with a damaged wear ring will feel like it’s slipping when you give it gas, or it feels like it’s not wanting to catch.

What Can Damage a Wear Ring or Pump?

Sucked up something in pump wear ring

The things that can damage a wear ring or pump is sand, rocks, and anything that is in the water. I’ve even seen someone suck up a map of the lake before. 

You could also have seaweed wrapped around the driveshaft or even a tow-rope around the drive shaft, keeping it from spinning correctly or blocking the flow of water.

If the next question you have is “why don’t they put a grate in front of the intake to block such debris” then I have a post here that you should read.

The Off Chance

Then there is the off chance that your pump on your watercraft is not making a perfect seal to the body.

When this happens, it just starts sucking air, and it will be slow to take off. This is rare to happen and doesn’t usually happen on its own. It happens when the pump is not put together correctly, which is super rare. This whole pump not lining up is so rare, I was not going to put it in. 

Another oddity but does have a greater chance of happening is a spinning wear ring. The wear ring fits super tight in the housing and the tolerances between it and the impeller are super tight – it’s got to be if you want proper thrust. Sometimes the wear ring will start to spin and make things all crazy.

Pump Damage = Repair Shop

The bad news is many of this stuff listed above will require a dealership or a repair shop to fix.

Anything that deals with the pump should be done on dry land by a professional, especially if you have iBR or RIDE on your watercraft, as those make it a little harder to get to the pump.

Sometimes you can get lucky with rope sucked in, but don’t flip it and don’t remove the intake grate. Also, you can NOT get to the pump from the inside of the engine compartment. If you don’t know what you’re doing, let someone who does do it.

2-Stroke Clogged Carburetor

If you have a 2-Stroke, then it could be a clogged carburetor. This is common if you had the watercraft sit for a couple of months. A clogged carburetor will struggle to run, not want to run, or not start at all.

Another one could be the fuel lines are rotting away. The way you check that is by turning the fuel knob to reserve, and if it runs fine on that, then the fuel lines need to be replaced. Note: only 2-Strokes will have a fuel knob.

If you have a 2-stroke, then you should also check out the “engine trouble” section below too.

Bad Gas

I’ve seen water get in the gas tank and cause it to run horribly or not want to take off. Sometimes it would even have the jet ski stall out. Ethanol in gas is making this problem even worse.

Water sometimes gets in the gasoline even at the gas station’s tanks. Your car is less picky about it, but a jet ski will complain.

The most common way people get water in the gas is from rainwater. Sometimes they don’t put the gas cap on tightly or the gas jugs they use are stored where water can get to them.

Gas Expires

Another point about gas is that it expires quicker than you might think.

If you don’t put a fuel stabilizer (Amazon Link Ad) in the gas after you store it for several months, then the gas goes bad.

Don’t expect to go away for a month or two and the gas to be good; long-term storage should have the jet ski winterized. Jet skis are high-performance engines, and they get picky if they don’t have the correct amount of octane in them. You can try some fuel treatment if you suspect it’s bad gas, but if water is in there, you need to get it all out and put fresh gas in.

When it comes to getting the gas out or anything related to gas, I recommend taking it to the dealership or repair shop. Gas is DANGEROUS and highly explosive and should be done by a professional.

High Performance = Premium Gas

If you have a high-performance jet ski, one with a supercharger or says, “SVHO” then it’s picker about what gas you give it. A bad supercharger can cause a jet ski to not get to top speed.

Some watercraft will show a check engine light if you run too low of an octane gas in it.

Even if the manufacturers “says” you can run regular, I would still put in premium.

Sure, it can run on regular, but it doesn’t run well unless you give it the proper juice. It’s like saying someone can run in sandals, sure they can, but they run better in sneakers.

Engine Troubles

You could have a fuel pump going bad or, even worse, the engine is blown.

A blown engine is rare but more common on 2-Strokes. It’s rarer on modern 4-Strokes unless the engine was just never taken care of or you keep it in a harsh environment like saltwater and never clean it. 

If it’s engine trouble, you need to let a professional look at it. 

Taking on Water

If the watercraft is half full of water, then it’s going to be slow to take off.

Take the seat off and see if any water is in the hull. If you got water in the hull, then it’s time to get it to dry land and let a professional look at it.

Make sure you have the drain plugs in, and you keep a cover on your watercraft when you’re not using it.

Wrong Modes or Keys

This is an interesting one.

You could be in the wrong mode or using the wrong key. Many jet skis will come with different riding modes or a learning key. 

Before you go riding, check to see if you have an “L-Key” or “Learning Key” as those will restrict take-off and top speed. Some watercraft even have the learning mode built-in and will have a light turn on saying “L-Mode”.

If you have the correct key, then it could be the driving modes of the watercraft. With so many jet skis getting faster, and faster, manufacturers have included different driving modes. The default mode is usually a “Touring Mode” which is a slow takeoff. You also have ECO mode, which is a slow takeoff and limited speed, but this mode has to be activated by you pressing a button. Only the Touring Mode is the default mode. Locate the Sport Mode button for full power acceleration. 

Learn more about modes and keys here.

If it’s not the modes and the key says it’s not a slow key, then it could still be the key. If you had just bought the PWC from the dealership, they could have programmed the keys wrong. Try the other key to make sure they didn’t get them backwards. A tip is that the watercraft will tell you when you first put the key on what type of key you have connected. You want the screen to say “Normal Key” or something along those lines.

You’re starting to see watercraft not come with learning keys from the factory anymore, as this was a common problem. You can still get learning keys if you need them for an extra charge, but I usually end up making all my keys programmed as fast keys and never tell new riders about sport mode.

Takes Off, But No Top End

I thought I should add this one just in case.

If the ski is lacking top end, where it takes off just fine but doesn’t go as fast as it used to, then it could be a bad supercharger.

If this is the case and the watercraft does fewer RPMs than normal, then I recommend you stop riding it and take it to a professional. Repairing a supercharger is not easy and should be done by a professional, especially if it has blown out.

If the supercharger is blown, then you could have metal pieces in the engine which will do more damage, and a professional needs to look at it.

Make sure the hoses haven’t blown off from the supercharger.

One Last Thing…

Above all else, take it to a dealership or repair shop. Those guys see this type of stuff all the time and will know right away what your problem could be.

Jet skis can be dangerous, and if you don’t know what you’re doing, let someone who does do it.



I started working at a power sports dealership in 2007, I worked in parts, service counter, and as a technician before moving to sales in 2013. I created in 2014 to answer common watercraft questions I would get from people. Now managing the site full-time, I continue to provide advice and web tools for my readers about watercraft. I've owned several watercraft, with a Sea-Doo Spark as my current main PWC.


  1. Hey guys just a quick question i recently purchased a 2004 rxp supercharged seadoo as its my first ski when i put the ski on foward it will start moving by its self without accelerating just wanted to know if this is normal thanks

    • That is normal, that model did not have iBR, but has a manual lever and when you put it in forward it will move forward at idle speed. When the engine is on, the impeller is spinning and the jet ski is always doing something. There is no true neutral or a real transmission, just a bucket that redirects where the water goes. Learn more here:

      • And also i had a little thin stick go in the impeller couldn’t take it out so i started the ski and it chewed it and i washed it out with a hose can this damage the ski or would i be alright i took it all out by washing it thanks for the reply and help champ

        • If it didn’t damage the impeller or wear ring, then you should be fine. You’ll know something is not right when you go to take off and the jet ski hesitates or “won’t catch”.

  2. Hi I have a 2018 seadoo spark. Worked fine until I put in 91 octane (was putting regular 87). Now with VTS at middle or low it won’t above 9 km (about 4000rpm) it just sputters and smoke out the back. If I put the VTS all the way up I can get it to take off, move the vts down and go but it’s not hitting its top speed. If I stop I need to start over again

    • I would check the pump to make sure you didn’t suck something up or have something stuck on the reverse bucket, which also controls your VTS.

  3. Hi I’m Carlos
    My wife’s 2011 wake pro will not take off fast ,it feels like it’s being flooded when you excelerate si you have to let go just a bit on the excelarator si it can get up and then you can go full Throttle don’t know what too do .

  4. Hi, I have (2) 2015 Sea Doo GTR215 that I picked up used. one runs perfect but the other wouldn’t get over 32 mph and hovered around 5k RPMs. The eco/sport modes wouldn’t change anything and it bogged around turns. What could be the cause? I didn’t see anything stuck or sucked up and it actually gets above 7.5k RPMs outside the water on the trailer.

    • The first thing I would do is make sure you’re not running a learning key on that model, as that is the speed and RPM’s a learning key would put you in. When you first put the key on, it will say “Welcome…” and then tell you what key is on it after that, either normal or learning key.

      • It definitely is the regular (yellow) key. I even reviewed the computer key settings and noted that L key was 3 and Reg key was set at 5. How about a spark plug or bad gas over the storage season issue?

        • A fresh tank of 93 octane gas and new spark plugs is always a good idea at the start of the season. I would also check to see the ignition coils are all the way down and connected properly. I’ve seen a Sea-Doo run fine on the trailer but when the customer went to launch it the thing didn’t run right and it was all because one coil was not seated properly.

          If you’re able to see the L Key settings 1 to 5 with the engine off then you for sure have the fast key on it, only the fast key can program the others. The “R Key” is rental so no need to adjust that one unless the key was programmed as rental. Any DESS keys can be programmed to regular, learning or rental. It was common to have customers program one of their fast keys as learning or rental to trick their kids and family. This is why I have people put the key on and wait for the gauge to tell them what key they put on. Sport mode should be a quicker take off compared to touring mode, both modes reach the same top speed. Since it’s GTRs I would also check out the supercharger. If that doesn’t work it’ll need to be hooked up to a computer at the dealership to see what codes it’s throwing.

  5. hello i have a 2013 seadoo rxt-x260. i was in the water an it was running perfect but it just stop going it turns perfect and it revs perfect to but won’t go forward or revers. i check the impeller see if it spinning an it doesn’t spin when you give it gas. check and everything i clear from the pump


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