HELP GTX DI limited RPM

[alexandria]

I know this issue has been discussed several times but what the ski is doing is somewhat different from other posts. This is forum has been very helpful in dealing with the Direct Injection model (very painful ski)

After riding it a few hours this season, the ski showed the MAINT with alarm every minute and RPM dropped to 4900 RPM. I started it several times with the same issue every time ... Suddenly, it's back to normal with no alarm or MAINT for an hour however, it reached 6900 RPM but there was some loss of power ( lag in getting up to speed after reaching a high RPM ... Next day, It showed the same issue again ( MAINT, alarm and low RPM 4900RPM, loss of power). Checked the impeller and was clear, Checked compression on both cylinders (130 / 127 psi) ..... I noticed that when you flush it, the engine hesitates and can stall every time I try to flush it with freshwater. Also, the drowning mode is not active on the ski (when you press the throttle fully, no alarm and you can still hear the fuel pump working)

Is it one of the Throttle Position sensors
Is it the Water pressure regulator
Any other suggestion PLEASE


I appreciate your help and support

 

[WaarrEagle]

Sounds like you need a CanDooPro to check the trouble codes.

 

[XPLORx4]

My '02 GTX DI has done the same thing- show MAINT light and go into limp mode intermittently. It will run fine without any issues for several multi-hour trips out on the water, and then suddenly, it'll throw the MAINT code. I ended up buying CanDooPro to help troubleshoot the issue, and I found that the errors are related to low voltage. The problem could be a dirty electrical connection or the rectifier.

In your case, I would advise cleaning all of the battery terminals and cables first. If you cannot obtain the CanDooPro hardware/software, try hooking up a voltmeter to the battery to monitor voltage while riding. If the voltage ever drops below 12.8 while the engine is running, the problem could be the rectifier.

 

[XPLORx4]

I noticed that when you flush it, the engine hesitates and can stall every time I try to flush it with freshwater.

Be sure to start the engine before turning on the water, and turn off the water before shutting off the engine. You can run the engine for about 15 seconds without water.

 

[jhjesse]

Sounds like your rectifier is being pushed past it’s limits at times probably because the fuel pump is demanding a lot of voltage.
The reason your fuel pump is demanding so much voltage is most probably because the filters need changing, as well as, fuel pump cleaned. A candoo pro would most probably verify this.

If it were me I would pull the pump and clean it, change all three filters and replace the rectifier with a new OEM rectifier.

 

[alexandria]

Thank you XPLORx4 very much for your reply. I'll try to test the voltage while riding ... should I hook up the voltmeter to the battery or to the cables going to the battery? or it doesn't matter
What else other than the low voltage should I look for (exceeding maximum voltage, fluctuation, or else)?

 

[alexandria]

Sounds like your rectifier is being pushed past it’s limits at times probably because the fuel pump is demanding a lot of voltage.
The reason your fuel pump is demanding so much voltage is most probably because the filters need changing, as well as, fuel pump cleaned. A candoo pro would most probably verify this.

If it were me I would pull the pump and clean it, change all three filters and replace the rectifier with a new OEM rectifier.

This sounds interesting as the ski has been sitting for almost 5 years with a few gallons of gas in the tank. I added fresh gas before starting it this year. It fired up right away and had no issue for about 4 hours. Unfortunately, removing and cleaning the fuel pump is a bit difficult for me. The OEM rectifier is very expensive ($194) ... there are much cheaper options on amazon. can I use one of these Amazon.com: Kemimoto Rectifier Voltage Regulator Compatible With Sea Doo 1998-2002 GTX RFI 800CC 2000-2003 GTX DI 951CC 278001554 278001241: Automotive

 

[jhjesse]

I don’t know of anyone who has had luck with the cheap Chinese made rectifiers. Might try OSD parts. They carry a heavy duty 4tec rectifier with plugs made for DI skis.

 

[XPLORx4]

Thank you XPLORx4 very much for your reply. I'll try to test the voltage while riding ... should I hook up the voltmeter to the battery or to the cables going to the battery? or it doesn't matter
What else other than the low voltage should I look for (exceeding maximum voltage, fluctuation, or else)?

Make sure the battery terminals and connections to the battery are clean and not corroded. Measure voltage at the battery terminals.

 

[POPPS]

Aftermarket regulators usually work. It's also possible that the pump is going, and drawing too much current, which will also trigger the voltage maintenance code and limp mode.

 

[nickmo12]

I've owned my DI since new 19 years. I lost count of how many rectifiers have been in my DI. I can tell you that I've had OEM rectifiers, a couple of OSDs and cheap ebay units and can honestly say there is not much difference in longevity. I carry a spare onboard.