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Discussion Starter #1
So I Downloaded a PDF manual for my new to me 2008 crossfire 1000 because when I bought the machine yesterday the sled threw code 18 on the dash. This code is Power valve motor problem. The Manual described to energise the servo motor with 2 test leads to a separate 12 volt source and reverse polarity to turn motor opposite direction. motor checks out good, next do ohms test to motor itself turn motor and read resistance threw entire cycle and both original motor and a spare that came with the sled check out a ok. checked and adjusted both power valve cables to the 35mm length specified in the book. Next removed power valves checked for damage worn spots on the slide shaft cleaned and made sure were freely moving up and down in the channels. Next book says to remove spark plugs and quickly pull cord with multi meter checking for 12 volts dc at the plug. Now here is where it gets interesting there is no voltage present at the plug when either you pull over the engine by hand or unplug and do the test with the engine running so I figured has to be broken wire. Totally disassembled half the sled to trace the wires because they go under the gas tank trace all 5 wires back the left plug on the ecu do continuity test all wires check out a ok. but NO voltage at any rpm. what else could it be?everything seems to be operating very well on the sled but the power valves are not opening and its evident because of the lack of power on the top end. and the servo motor wont turn.
 

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On my ZR 800, there is a servo motor regulator and a condensor. I discovered them when trouble shooting a bad servo motor on my sled a couple years ago.
 

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Discussion Starter #3
Thanks for the info on the old post but Unfortunately I can't do any of the tests described because I don't have a regulator and condenser like your older carb machine has. In my case the Crossfire has a CCU module that took over all the jobs that the old school regulator did and since all the lighting works and engine runs it leads me to believe that box is fine and its my ECU not sending the voltage information to the servo motor. My best guess is that that the TPS sensor is sending the information to the ECU because the sled will drive and speed up but from there its not Sending the Information to the servo motor to turn and open the Power valves. Hoping someone else has any ideas or my ways to diagnose.
 

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Unfortunately the code its throwing isn't specific and there is no way to test the ECU. I'm guessing that getting a known good ECU to swap and test, isn't a possibility? Sorry, I'm not an EFI guy, but I would think swapping the ECU would be the only thing you could try.
 

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On the firecat, the power for the APV motor comes from the voltage regulator, it is rectified to DC voltage and fed to the ECU.

Attached is a diagram for the 04 firecat, for reference. This isn't the correct diagram for your sled, but gives you an idea. You can check to see if you have voltage coming in at ECU, and eliminate either VR or ECU as culprit. Screenshot_20191107-123316_Drive.jpg
 

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Discussion Starter #7
A little time laps on the crossfire project. Bypassed the apv system and went to full Piston style STM power valves. Almost a grand later after converting to Can$ sleds up and running better then it was with no more ecu code 18 and most definitely more responsive. But here is the new problem the sled still reacts like it has a rev limiter on at 6000 rpm or higher it pops and studders and no more acceration. Just so happened I keept in Contact with the previous owner sent him a vid of the sled running and he assured me with a video of his own the sled should not be doing this. Now before I go throwing more money at it I need some suggestions.

Other posts mostly are saying maping in the ecu for fuel on the top rpm range have taking a crap. And running lean causing limp mode.

Others say stator is on its way out but that's hard to believe since everything electric works other then left hand warmer.

Please is there anyone else out there that has had this issue before.
 

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Discussion Starter #8
Called my local cat dealer and described the symptoms to the mechanic, he said bring the sled in they will do a reflash costs 45$. And should solve the problem but, How dose a computer just loose part of its memory? and not all of it? I know in the auto industry cars can revert back to previous setups it the battery is disconnected for a period of time. But the next time you start the car it runs like crap and the ECU self diagnoses and starts to run better in a few min. What is so special about a snowmobile that it can rewrite and self learn its parameters again?
 

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I agree with you, i think your problem isn't likely ecu, likely be a waist of money. Get the wiring diagram for your sled, and u can backprobe werher the ecu is getting the power it needs to drive servo, and if its outputting it to servo
 

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Discussion Starter #10
I did that. downloaded the pdf repair manual traced all 5 wires back to the ecu did continuity test they check out but the ecu is not sending voltage to the servo motor. so that is why I bypassed the whole setup and put the stm Piston power valve kit on. In the kit it has a plug that is put in where the old servo motor was plugged in and it tricks the ecu into thinking the servo motor is still there. this made the sled run much better at low speeds and make it much more responsive but it still wont rev over 6000RPM and when you try to accelerate anymore it sounds like its bouncing off a rev limiter.
 
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