I picked up a 2002 SeaDoo GTX 4 tec from a guy who got it from another guy. So the history was kind of unknown. The guy said that he bought it as a project and took it to the dealer for repair and they told him it had an engine with rusted cylinders and the ECU was bad. I brought it home and sure enough there was water in the cylinders. I removed the spark plugs and it would just keep spitting out water like a dolphin with three blow holes, it never seemed to end. Pulled the intake and found it had a LOT of water in it. Pulled the engine found starter bendix missing 2 teeth, pulled head, bores looked good, replaced head gasket, bendix, set cam timing with manual, put engine back into ski. I tried to start it and as soon as it begins to start, the bendix kicks out and it does not start. I will post a youtube video later because I think that would better explain what it is doing.
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2002 GTX 4 tec project refuses to start HELP
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Hawk388
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Did you change the oil? It requires about five flushes to ensure all water is out of the engine.
Were the cylinders rusted? If they were and you've done all this without honing out the cylinders and addressing any rust pits in the cylinder walls, you've likely broken the piston rings and it isn't getting enough compression to fire off.
When cylinders are rusty like you explained, the injectors are usually trashed as well. Did you flow check the injectors?
Did you replace the spark plugs? Did you try starting with a plug pulled out and connected to see if you're getting spark?
There are so many unanswered questions here.
Edit: Also, since you had the engine out, did you check the connecting rods to see if they were bent? Did you have the head checked for cracks?
Were the cylinders rusted? If they were and you've done all this without honing out the cylinders and addressing any rust pits in the cylinder walls, you've likely broken the piston rings and it isn't getting enough compression to fire off.
When cylinders are rusty like you explained, the injectors are usually trashed as well. Did you flow check the injectors?
Did you replace the spark plugs? Did you try starting with a plug pulled out and connected to see if you're getting spark?
There are so many unanswered questions here.
Edit: Also, since you had the engine out, did you check the connecting rods to see if they were bent? Did you have the head checked for cracks?
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From the 2002 SeaDoo service Manual
Resistance Test
Disconnect the CPS plug connector from the wir-
ing harness and check the resistance of the sensor
itself.
The resistance should be between 190 Ω and 290
Ω.
Otherwise, replace the CPS.
If resistance tests good, reconnect the CPS and
disconnect the EMS ECU connector A on the EMS
ECU.
Using a multimeter, recheck resistance value be-
tween terminals 5 and 19.
If resistance value is correct, try a new EMS ECU. Resistance value was correct!
Refer to EMS ECU REPLACEMENT procedures
elsewhere in this section
It's starting to look like I may need an ECU
Resistance Test
Disconnect the CPS plug connector from the wir-
ing harness and check the resistance of the sensor
itself.
The resistance should be between 190 Ω and 290
Ω.
Otherwise, replace the CPS.
If resistance tests good, reconnect the CPS and
disconnect the EMS ECU connector A on the EMS
ECU.
Using a multimeter, recheck resistance value be-
tween terminals 5 and 19.
If resistance value is correct, try a new EMS ECU. Resistance value was correct!
Refer to EMS ECU REPLACEMENT procedures
elsewhere in this section
It's starting to look like I may need an ECU
I cleaned all battery and ground connections. I then disconnect the positive lead on the starter and connected a spare positive cable to a good battery and engine ground, it cranks normal that way. Once the computer gets involved it cranks like in the video, almost starts, then the starter lets go. I pulled the injectors and sprayed starting fluid in each hole, replaced injectors and still no change.
I did every resistance and voltage test I could using chapter 7 of the factory SeaDoo manual. Every sensor I could test, passed, and no issues with the wiring harness. The manual suggests replacing the ECU, but that is an expensive gamble
Is there any sure way to test an ECU?
I did every resistance and voltage test I could using chapter 7 of the factory SeaDoo manual. Every sensor I could test, passed, and no issues with the wiring harness. The manual suggests replacing the ECU, but that is an expensive gamble
Is there any sure way to test an ECU?
I called the dealer that looked at it last and they pulled the paperwork and said he remembered them looking at it. The service guy said they swapped an ECU onto it and the ski ran, so he was 99% sure the ECU needs to be replaced, cost $750 plus 1 or 1.5 hours labor= about $900-1000 with tax.
There are only a few on ebay and they want $650 with the DESS key, $550 without which is about the same after a trip to the dealer for key programming.
There are only a few on ebay and they want $650 with the DESS key, $550 without which is about the same after a trip to the dealer for key programming.
Update, I bought a used ECU without key from eBay, and CanDooPro Home Edition. Replaced the ECU, used the CanDooPro to program my keys to it, the ski starts but refuses to idle, throws codes P1611 and P0608. I removed the idle bypass valve and it was corroded and probably not functioning which would explain the poor idle. I ordered a complete throttle body from eBay and will swap that once it arrives and hope that cures the idle issue.
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