1993 seadoo xp starts then stalls as you let go of the starter button

[PDUDDY660]

1993 seadoo xp 650 brand new engine, 650 i think, carbs, fuel lines and gas and oil, sat for 3 years, starts and then you let go of the starter button it stalls, if you hold the button down you can rev it up and will stay running good as long as you hold the button down. Need help. This is electrical, i am a automotive tech so i know my way around, but now seadoo electronics. Seen a old post for the same problem but no one answered him. Any ideas thanks.

 

[Strizzo]

check connections for a bad ground or bad connection somewhere, especially in the area of the solenoid.

 

[PDUDDY660]

I went throw the hole entire electical system, all connections and grounds seem great. It was garage keep and well maintained with low hours, but i will go throw it all again and check everything again. The local dealer wont even touch it they said its to old.. So im on my own.

 

[92 SeaBomB XP]

I have a 92 XP with the exact same problem... It runs great until I let off the starter button! Have you found a solution to this? I read somewhere that replacing the mpem (computer) may resolve it, but I hate throwing parts at a problem without proper diagnosis of it. All my electrical connections look good, but I haven't done any testing yet.

 

[Mekanix]

Do you have the main positive wire on the solenoid on the wrong lug ?.

Think about it. It will only give power to the electrics when the starter is getting power.
This one fooled me once.
It would do the same thing but wouldnt start or beep. Turns out the previous owner replaced the solenoid and put the positive wire on the output side going to the starter and not the battery.

 

[92 SeaBomB XP]

Do you have the main positive wire on the solenoid on the wrong lug ?.

Think about it. It will only give power to the electrics when the starter is getting power.
This one fooled me once.
It would do the same thing but wouldnt start or beep. Turns out the previous owner replaced the solenoid and put the positive wire on the output side going to the starter and not the battery.

Good Point, I will try to switch them around tommorrow and see. I tested the kill switch and tether switch tonight and both are fine. I just bought a new battery and I'm getting it all charged up for tommorrow. I think that the mpem may need to stay above 12V to operate and I'm not sure it was getting that. Tommorrow I'm also gonna run the resistance tests on the mpem itself. I'm hoping that's not the problem because it's list price is like $550! I'm suprised that it's having this problem because all of the connections I've seen have been perfect. No corrosion anywhere. I didn't look into the magneto yet though.

 

[92 SeaBomB XP]

Just wanted to update for everyone else that I bought a new battery and got it filled and charged. Today I installed it and its running great! The MPEM needs to be fed the constant 12V from the battery to stay running.

 

[AdamXP800]

Im glad you got it going!! I think ive heard anything below 10.5v and the MPEM will not function correctly