2001 RXDI dies immediately

[ajdrr]

Hi All,
New to the board.. need some advice
I have a 2001 RXDI that has been working great. Last weekend after idling for a few minutes, it died. No power to the gauge. The start button works, engine turns, catches than dies in less that 1 sec.
Plugs out - cranks fine - mist from DI's
Injectors working
Rave clicking like normal

As soon as it starts, power to the speedo turns off. It is like the engine power is shut off as soon as it starts.
It will do this a million times, over and over. The start button disengages as soon as it starts, like normal.
Any ideas? No messages or lights on speedo.

 

[Dr Honda]

Check the voltage while trying to start the engine. If it's dropping blelow about 10.6~11v... then the MPEM may just be reseting.

As far as no gauge.... check all the fuses.

 

[ajdrr]

Check the voltage while trying to start the engine. If it's dropping blelow about 10.6~11v... then the MPEM may just be reseting.

As far as no gauge.... check all the fuses.

Thanks for the reply...

The voltage is about 11.9 to 12.3 during cranking - The power is on the gauge during cranking, set to RPM I can see about 500RPM while cranking, then when it starts, the gauge goes blank and the engine quits. I can press the start button again and the gauge comes on and cranks, starts and quits...over and over.
The manual says the MPEM disengages the starter when it hits 1000 RPM...this seems to happen, because if I hold the start switch the starter does not continue to run after starting and quitting.
With plug wires grounded, the starter will crank as long as I hold the button down.
Is there something that switches over to run mode after a start is sensed? a contactor or solenoid? Its like I pull the key off as soon as it starts. BUt the key is there and recognized..

 

[Dennis]

I would unplug the voltage regulator/rectifier and see if it stays running. I'm not sure where it is located on a DI.

 

[Dr Honda]

I wonder if the lanyard post has gone bad... and it's resetting the MPEM because of the vibration once the engine starts.

Try taking it out of the hull... and holding still when starting. Otherwise... disconnect the voltage regulator from the system. If it's passing AC voltage... it will cause the MPEM to go crazy.

 

[ajdrr]

Same thing, quick start immediate die, with two Vreg connectors unplugged, and while holding lanyard post and key firm.
What happens after the starter is disengaged by the box? is something else enabled?
Will a bad sensor or bad injector cause the engine to quit so fast? It literally quits in 1/4 second. It goves all the signs of being ready to start when I put the key on.

 

[Dennis]

I'm making sure of something here. Do you have to reset the key in order to restart the engine or can you just push the start/stop button?

 

[Dr Honda]

I'm making sure of something here. Do you have to reset the key in order to restart the engine or can you just push the start/stop button?

Nope... you should be able to just restart.


Unfortunately... since the system is resetting... if it's not a loose connection somewhere... then the MPEM has gone bad. Although... I've never seen this issue.

 

[ajdrr]

Thanks for all of your advice.

Yes, I can just push the starter again and it repeats endlessly. Start, die, start die,...
I am going to go through the sensor resistance list and check all of the wiring I can.

Any more advice is greatly appreciated

 

[Dennis]

I realize how it is supposed to work. I was just making sure how it is working in this situation.
It doesn't turn off as if you pulled the key. It turns off as if you pushed the start/stop button right after start up. Strange, very strange.

 

[Dennis]

I'm thinking the MPEM has gone bad also. I guess there's a slight chance the INFO GAUGE is causing some kind of unwanted feedback to the MPEM. Unplug it and see if that helps.

 

[ajdrr]

Info unplugged, same thing.
YEs, it is like I hit the start button immediately after starting.
CAn I assume that the DESS security is ok and the key is recognized? Since it chirps twice and spins up the fuel pump and clicks the air solenoid twice?


Correction; Key goes on two chirps and fuel pump spins up for 2 seconds.
After start and fail, air solenoid clicks twice. Then I can press start again

 

[Dennis]

The DESS is working fine. If you had to reinstall the key after shutdown then I would think otherwise but you don't.
I would do an ohm reading on the start/stop switch. Maybe it only partially breaks the connection when you release it and MPEM sees that and shuts off the engine. If that checks OK then I'm thinking it's time for a MPEM

 

[ajdrr]

Stop /stop ohms out ok, short when pressed. I also can keep the start button depressed after it starts/dies, the system disconnect the starter. Don't need to reinstall key.
MPEM sounds expensive any suggestions where to get one?

 

[Dennis]

You say the stop switch is shorted when depressed but is it a TOTALLY open circuit when released?

 

[ajdrr]

Yes, shorted - 5 ohms or so, and greater than 2 MegOhms when not pressed. When disconnected. Why? should there be a resistance when unpressed?

Another thing... The MPEM connector pinout is not the same as the one in the 2001 shop manual. I checked the fuel injection wiring and they goto different pins, all of the others are also different. Same connector #4, but different pins. Is there a correction ?

 

[Dennis]

I can't explain the difference of the pinout.
One last thing. I would unplug the start switch from the harness, install the lanyard and use a jumper (needle nose pliers) to start the engine. This will eliminate the switch as a the problem for sure.

 

[ajdrr]

Thanks to Dennis and Dr. Honda for all the help.
Unfortunately, I gave up today and towed to Seminole power sports..
They called and said it looks like the air pressure regulator on the fuel rail.
225 for the reg and 200 for the diag and labor.
Odd thing was they said they could either do a confirming check, but a $275 airhose might break, or replace the air reg. Their guru (15+ years) thinks it will work, if not I have a new air reg and still a broke ski.
I will know in 4-5 days when they get the part.

 

[Dennis]

I hope it all turns out OK. Their diagnosis seems strange. Seems to me that you are having a electrical issue and I don't see how a air regulator fits into that kind of a problem. Report back with the results. :cheers:

 

[houseofcash]

Thanks to Dennis and Dr. Honda for all the help.
Unfortunately, I gave up today and towed to Seminole power sports..
They called and said it looks like the air pressure regulator on the fuel rail.
225 for the reg and 200 for the diag and labor.
Odd thing was they said they could either do a confirming check, but a $275 airhose might break, or replace the air reg. Their guru (15+ years) thinks it will work, if not I have a new air reg and still a broke ski.
I will know in 4-5 days when they get the part.

Hmm, very strange they think it's the air regulator. I just had this part replaced on my 2000 rx di. However I was not experiencing what you are. My machine gave a "Maint" warning while out on the water and would go past 4000rpm when acceleration was first pressed. Once released and pulled again she would take off. After about 15mins of this,she stalled out. Started again no prob. Then when coming back to port stalled out again and took abit to start again.

Dealer thought it was voltage regulator, however was not the case. Turned out it was the air regulator. Since getting it back. She runs great! I was fortunate my repair was still covered under warranty.

Best of luck to you
House

 

[ajdrr]

Hi All,
Just got my boat back, yes some 4 weeks ago. They said it was the air pressure reg on the fuel rail. It was NOT, so yes then I had a 450 new air reg and a ski that still don't work. It ended up being the air compressor, cylinder scored fuel backflowing.... 400 labor 625 parts including new air reg I didn't need. They also said they heard knocking and I should go for a top end, which was done by a real pro 1 year ago...Ran it today for 2 hours at top speed.... it's nice to have her back :cheers:

So,
Won't start but catches and dies....
Plugs out front cyl puffing misty gas, back cyl puffing mostly only air sometimes mist...
all diags fine, even on dealer code computer - air reg failed 1 of 3 times was only code....

Odd problem stumped the pros.... I hope posting this helps someone save a few bucks...would have been only 500-600 for a new air comp.
Again, thank you all for so much help for a newbie. You guys are a class act. I will stay a member and try to help whoever I can...