GTX supercharged starts runs 3 seconds then dies

[AlexCarr]

I have a 2004 Sea-Doo GTX supercharged motor. The vehicle started up and runs for 3 seconds and then dies. It had a code for Oil pressure switches that I changed both out with new ones. But I still have the issue and codes are in the computer. I took it to a person who knew tons about the Skis and he was at a complete loss. I really hope someone on here might be able to help me. I do have spark, compression, and fuel.

 

[mkov608]

Download the service manual for your ski from Seadoo manuals . net and follow the procedure to check your fuel pressure. You should see 44 PSI when you put the lanyard on the DESS post; if the fuel pressure is good during those 3 seconds when it's running, you can eliminate that as a cause. You may have fuel initially, but the pressure may be insufficient to keep it running.

 

[AlexCarr]

fuel pressure

I tested the fuel pressure multiple time and it would not go any higher then 40psi but with attaching key it would go to 40 and with cranking it would go to 40 and stay.

 

[RXTAS Rider]

Assuming your getting enough fuel for idle have you verified the ignition is still firing past 3 seconds? If the computer is thinking the oil pressure is low it may be killing the engine to prevent damage. Im not a seadoo expert yet but i have 18 years in drag racing and off roading and thats how i would start.

 

[Coastiejoe]

I'm betting this will come back to either the MPEM or data that the MPEM is not getting.

Get a noid lamp and connect it to the injector input. See if it is being told to turn off after 3 seconds. Do the same with a spark tester. Got to find out a known good or known bad before we can figure things out.