2006 FX HO Cruiser

[Don King]

I am new to this forum . Has anyone here had one cylinder stop triggering the coil to fire? I bought this ski and rebuilt the motor. It fired up and ran immediately but after I took it out the speed was only 35mph and 8000rpm. There are no codes, no oil in the water , no bad coils or plugs and all good compression. I am trying to determine if the ECU is bad or not. Hoping that the YDS 1.33 I ordered will help me figure that out. I think the engine is not the problem but maybe a ground wire that feeds the ECU. The positive wire to the coil is reading over 12 volts. I am waiting for tools to test the negative pulse from the ECU.Anyone here have a similar experience?

 

[robert843]

If the compression all checked out I would give the pump and the impeller a good looking over make sure the impeller isn't rubbing against the ware ring and the impeller looks good. Also double check the key doesn't have it locked into learners or eco mode.

 

[Don King]

Thanks for the response. The jet pump is in good shape. I checked it while the engine was out. The motor is running on 3 cylinders with no spark to that one coil. I switched the coils and plugs around to other cylinders and they are all working. At this point, I believe that the negative pulse from the ECU to the Coil is not pulsing as it should in order for the coil to make spark to the plug. The coil has 12v but the negative pulse grounding comes from the ECU. Complicated mess.

 

[Don King]

Also the remote does work and change from normal to learners mode . Pretty sure the lost 2000+ rpm is due to the dead cylinder coil issue.

 

[robert843]

Ok if your sure a cylinder is not firing I wouldn't be much help on that. I think there was a known issue for that model year of a Ecu failure causing the third cyclinder to not fire but I'm not overly familiar with it but I'm sure someone else can chime in on that or correct me. If it was that issue the only resolve I recall was replacing the ecu but I could be way off.

 

[Don King]

Thanks for the comments. Looking that way.

 

[Ronnie]

If you think it is the ecu consider sending it to Carmo in Chico CA for a diagnosis and possible repair. They couldn't fix mine (ecu for an 06 non ho fx cruiser) but have repaired others. Check their website to be sure they have successfully fixed your model ecu. Last year diagnostic cost me about $80 including shipping both ways. A repair would have been about $320 total. As you may already know a new ecu runs close to $1,200. I've seen used ones on eBay for $300 to $600 but would be reluctant to buy a used one "as is".

 

[Don King]

I'll check them out. I don't want a used one unless I saw the ski running. What was the problem with your ECU/Cruiser?

 

[Ronnie]

Never found the root cause of the problem but two pwc techs narrowed it down to the ecu after ruling everything else out. Even Carmo sent it back with an unrepairable note after having it for a few weeks. They drilled and filled the cover but never stated what was wrong with it.

 

[Don King]

Didn't find my model on their web site any way. I'm going to check all of the ground wires. Might have left something loose.

 

[robert843]

Another great spot to look for info is Greenhulk.net

 

[Don King]

I have asked about it on Greenhulk but so far no help. Computers are like a foreign language to most of us.

 

[Don King]

Just to let all know. I ordered a Computer with wiring harness from an 08 model. The ski is now repaired. I offered 1/2 price to an ebay seller for the computer and harness and he took my offer. Anyone who is thinking about buying the Yamaha diagnostic software should just buy it. You can do alot with it. Thanks for your help.

 

[robert843]

Glad you got it fixed I figured the same it needed a new ECU.