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Sea-Doo Won’t Start or Accelerate [Sea-Doo Troubleshooting]

Sea-Doo Won’t Start or Accelerate [Sea-Doo Troubleshooting]

It’s always a pain when you attach the key to your Sea-Doo, push the start button, and… nothing happens.

Even if you maintain it perfectly, malfunctions may occur.

Since some of them could be easily avoided, you would probably like to know how to troubleshoot your Sea-Doo yourself.

For your convenience, we at JetDrift have compiled the most common issues causing a Sea-Doo not to start or accelerate, and what you should do about them according to the manufacturer.

To learn more about what causes these issues, you may also want to check into Sea-Doo beep codes and fault messages as well.

Why is My Sea-Doo Not Starting?

There could be many reasons why your Sea-Doo won’t start. Possible causes could relate to electrical issues like problems with the spark plugs, fuses, battery, wires and connections. Also, the gas could be stale or contaminated, or the fuel line may be clogged. Finally, a faulty starter could also be why you can’t start your Sea-Doo.

Beyond the problems with starting, you may have other problems like your Sea-Doo isn’t accelerating properly, it’s smoking, or overheating.

First, let’s discuss these issues one-by-one and briefly explore the possible causes.

The possible reasons why your Sea-Doo:won’t turn over at all:– Wrong D.E.S.S key

– Battery problems

– Electrical issues

– Burnt fuses

– ECM (Computer) malfunctions

– Faulty starter

cranks slowly:– Battery problems

– Loose connections

– Wrong starter

turns over but won’t start:– Spark plug issues

– Burnt fuses

– Bad fuel/low fuel

– Engine malfunctions

– Clogged fuel line and injectors/carbs

engine misfires and runs irregularly:– Spark plug issues

– Faulty ignition coils

– Bad fuel/low fuel

– Engine malfunctions

– Clogged fuel line and injectors/carbs

starts but won’t accelerate:– Learning key/ECO mode is in use

– Clogged pump/intake

– Engine oil level is too high

-Damaged impeller or wear ring

– Weak spark

– Fuel and fuel line issues

– Supercharger problems

– ECM or engine malfunctions

– Clogged air filter

smokes:– Engine oil level is too high

– Damaged head gasket

– Water in the gas

– Coolant leak

– Engine damage

– Too rich a mixture (in case of 2-stroke Sea-Doos)

overheats:– Exhaust system is clogged

– Coolant level is loo low

– The connect adapter is left in the flushing port

– Low oil level

– Cavitation

In the following sections, you will learn more about these issues and their fixes.

It’s also highly recommended that you read the owner’s manual before you start servicing your Sea-Doo yourself!

Sea-Doo Won’t Turn Over

D.E.S.S. Key Issues

If your Sea-Doo doesn’t turn over at all, in many cases there is a problem with the key.

Make sure you’ve attached it properly. You can also try reconnecting the key because in many cases this solves the problem.

If your Sea-Doo still doesn’t recognize the key, you may be using the wrong key or it’s simply broken. If this happens, you will probably have to get it replaced or have the key reprogrammed by your dealer.

Electrical Faults

Another common reason why a Sea-Doo won’t crank is electrical issues.

Sea-Doos have many fuses and sometimes one of them is burnt. Check the fuses of the ECM, and electric starter, as well as the main fuse.

If your Sea-Doo still won’t start, you may want to check and clean the battery. If you don’t use your Sea-Doo very frequently, over time its battery is discharging itself, which means it probably just needs a charge.

If the terminals on the battery are corroded they also need a quick cleaning.

Reinstall the battery properly, making sure you don’t confuse the cables as this can damage the Sea-Doo’s electronic parts!

Warning: NEVER jump start your Sea-Doo!

If your battery is fully charged and the fuses aren’t burnt, carefully inspect the wires and connectors. Many issues can simply occur due to a loose connection, that’s why you should carefully check the whole electrical system.

ECM Malfunctions

Sea-Doo’s ECM, known as the ’Engine Control Module’ is simply the Sea-Doo’s computer. And just like any other part, the ECM can sometimes go wrong.

Keep in mind that a jump start or mixed-up battery cables can also burn the Sea-Doo’s ECM. That’s why you have to always be careful with the battery and avoid jump starts.

If your Sea-Doo’s ECM is burnt or broken you have to take the whole craft to your dealer or a service shop. If it needs to be replaced, be prepared for a $1000+ service bill.

The good news is that in some cases the ECM can be repaired. Many service shops can computer test the ECM and repair it if it’s possible.

Keep in mind that if a new ECM needs to be installed in your Sea-Doo all of your keys will need to be re-programmed as well.

Water-Flooded Engine

Has your Sea-Doo recently flipped over in the water? Or, have you just noticed a lot of water in the engine compartment?

If yes, water may be getting into the engine through the exhaust system. In this case, don’t even try cranking the engine as it may cause serious damage.

This is because a significant amount of water can cause a hydrolock in the engine, which simply means that water is blocking the pistons.

If you think that water has leaked into your Sea-Doo’s engine, you have to take it to a professional immediately.

Clogged Pump

Another common issue is when an object (rock, wood or other debris) blocks the impeller.

Since Sea-Doos have a direct drive system, so if the impeller is blocked you won’t be able to start the engine at all.

To solve this issue, try cleaning the pump yourself or take the craft to your dealer.

Sea-Doo Cranks Slowly

Another common issue when the Sea-Doo’s engine turns over, but it cranks slowly.

This is most often due to a weak battery or loose battery cable connections. Check your battery and charge it if needed.

Another problem could be a worn starter, which should be fixed or replaced.

Sea-Doo Turns Over But Won’t Start

There could be many reasons why your Sea-Doo turns over but won’t start.

Let’s see what the possible causes might be and how you can troubleshoot your Sea-Doo.

WARNING: The most important thing is to never crank the engine any longer than 10 seconds, as the starter is prone to overheating.

Fuel Issues

If your Sea-Doo turns over but won’t start you may just need to refill the tank.

Another issue could be if the gas is water-contaminated or went bad over time. In this case, you have to siphon the fuel from your Sea-Doo and refill it with fresh gas.

You may want to check the fuel pump and the whole fuel line as well, to make sure the gas is getting into the engine.

Spark Plugs and Burnt Fuses

It’s not only gas but sparks are also needed to start your Sea-Doo’s engine.

Remove the spark plugs and inspect them, as they could be fouled or defective. Clean or replace them if needed.

Also, check the fuses again and replace them if they’re burnt.

Engine Malfunctions

If your Sea-Doo cranks properly but won’t start, this could be a clue to an engine malfunction.

If this happens, you can check for a fault message on your dashboard and you can expect to hear a beeping sound as well.

Since Sea-Doo engine faults can vary widely, you should always read the fault code and refer to the owner’s manual for further guidance.

Sea-Doo Engine Misfires and Runs Irregularly

Even if you can start your Sea-Doo, the engine may sometimes run irregularly. Let’s see what the possible reasons are and their solutions.

Fuel Line

Best practice is to first inspect the fuel line. Make sure that the tank isn’t empty and refill if needed.

If you haven’t used your Sea-Doo for a while and you haven’t added fuel stabilizer then the stale gas can cause malfunctions in the fuel system.

Note, the gas in your tank should always be fresh and not water-contaminated. Deteriorated gas or other contamination can also clog the injectors, which can cause engine malfunctions.


Beyond the gas you will of course need sparks to fire up the engine.

If the spark plugs are fouled or defective this could be another reason why your Sea-Doo won’t start or run perfectly.

Don’t forget that the electricity for the sparks is generated by the ignition coils. If they have malfunctions you have to check and fix the stator on your Sea-Doo.

ECM of Engine Malfunctions

If your Sea-Doo’s engine runs irregularly, this can also be caused by an ECM or engine malfunction. Read the fault codes and follow the manufacturer’s recommendations.

Sea-Doo Won’t Accelerate

If your Sea-Doo doesn’t accelerate or reach its top speed it may be for the following reasons:– You are using the learning key. Solution: Use the regular key.

– Your Sea-Doo is in ECO mode. Solution: Always select SPORT mode for the best acceleration.

– Jet pump or the intake is clogged. Solution: Try cleaning it yourself or take the Sea-Doo to your dealer.

– The impeller or wear ring is damaged. Solution: Inspect and replace these parts if needed.

– The oil level in the engine is too high. Solution: Check the oil level with the dipstick and adust it.

– Weak spark. Solution: Check the spark plugs and the ignition coils.

– Fuel issues. Solution: Check the fuel condition, fuel pressure, injectors/carbs and the whole fuel line.

– Supercharger problems. Solution: Check the supercharger end rebuild if necessary.ECM or engine malfunctions. Solution: Read the fault code and follow the manufacturer’s recommendation.

Sea-Doo Engine is Smoking

If your Sea-Doo is smoking, beware that this always indicates a malfunction. The typical issues causing this are:– Engine oil level is too high. Solution: Check the oil level with the dipstick and adust it.

– Damaged head gasket. Solution: Inspect and replace the gasket if needed.

– Water in the gas. Solution: Drain the contaminated fuel and fill up the tank with fresh gas.

– Coolant leak. Solution: Check and fix the hoses and connections. Refill the coolant.

– Engine damage: Solution: Read the fault code and refer to the manual.

– Too rich a mixture (in case of 2-stroke Sea-Doos): Solution: Make sure you use the right amount of oil. 40:1 mix ratio works well for most 2-stroke Sea-Doos.

Sea-Doo is Overheating

Another common issue could be that your Sea-Doo is overheating. If this happens, here’s what to do:– Exhaust system is clogged. Solution: Even though Sea-Doos feature a closed-loop cooling system, their exhaust system and intercooler are still cooled with raw water. Attach a garden hose to the flushing port and flush the Sea-Doo according to the manufacturer’s recommendation.

– Low coolant level. Solution: Check the level of the coolant and refill if needed.

– Connect adapter left in the flushing port: Solution: Another lesser-known reason why a Sea-Doo overheats is if you leave the connect adapter in the flushing port. Make sure you remove it every time!

Low oil level. Solution: Refill the engine with the appropriate type of Sea-Doo oil.Cavitation. Solution: Check the impeller and wear ring for damage. If you have an aftermarket impeller, make sure it fits to the engine.


There could be various reasons why your Sea-Doo doesn’t start or work properly.

The most common Sea-Doo malfunctions are:– Your Sea-Doo won’t turn over at all.

– Your Sea-Doo cranks but doesn’t start.

– Your Sea-Doo misfires and runs irregularly.

– Your Sea-Doo runs but doesn’t accelerate properly/can’t reach its top speed.

– Your Sea-Doo smokes or overheats.

And their possible causes could be:– Wrong D.E.S.S key

– Battery or electrical system issues (connectors and wires, fuses, ECM)

– Wrong starter

– Spark plug or ignition coil issues

– Low fuel level or low fuel pressure

– Fuel is stale or contaminated

– Clogged fuel line and injector or carbs

– Wrong engine oil level

– Clogged pump/intake/cooling system

– Clogged air filter

– Damaged impeller or wear ring

– Supercharger issues

– Wrong coolant level

– Damaged gaskets

– Engine malfunctions

This is our short compilation of why a Sea-Doo won’t start or accelerate. We hope you found it useful!

As a final word, always refer to the owner’s manual or consult with your dealer before you start to service your Sea-Doo yourself!