900 isue

[overkill131313]

well my 900 has been working great last year and this year till yesterday. two days ago I changed the fuel filter and found out it was so pluged that I cant blow through it.(I cant belive it ran so good with this plugged filter on it)

so I changed filter and went to blue lake. it had a major bog in the midrange but it went away when I got up in elevation (5000 feet) it pulled hard with no stumbles at all all day. then when comming down it got the stumble in the mid range again. I almost think the plug filter was leaning it out and made it run so much better. anyone with a 900 have this problem? do I need to get a fuel controler to lean it out in the mid range? fuel controlers will do this? any info on fuel controlers would be great! anyone have a used one?

 

[geelak900]

Shouldn't be the case. I would check for throttle body boots cracked or loose, sounds like an air leak maybe. Had similar issues with mine, found one of the throttle bodies out of the boot.

 

[overkill131313]

boots look all good but if this was the case why does it run good over 5000 feet? it works great down low at wide open and just cruzing around. if you hold it at half throttle it sputters for 2 seconds then clears right up and gone. above 5000 feet it has zero sputter. this happened as soon as I took out the plugged fuel filter! I still cant believe how it even ran with the old filter. Im not jokin it is plugged, but ran way better at all throttle positions!

can you get an adjustable fuel regulator for these sleds? I know when tuning my Buick Grand National, just plus or minus a pound of fuel made a big difference! wondering if this has been played with on these sleds?

 

[geelak900]

Not real sure what would be related to the filter change other than maybe some debris went thru and is causing an injector to be slightly restricted?? I know on my 9 it always had a small midrange studder on the way up in elevation like riding up to the alpine from the parking lot. It almost seemed like the EFI was slow to compensate or something like that. Always ran great up top and never had the issue coming down. Last time i rode it it had the same symptoms but much worse and both up and down. I found one of the throttle body boots not seated properly likely causing a lean spot. Just be careful not to ride in in this spot for long, if it is lean it's dangerous......

 

[RockyMtn]

800 issue, 900 issue, sounds like it's just a polaris issue!!! Sounds like you can move your name from the guest book to the membership form now! Welcome to the club! LOL

 

[900sleddude]

I had a similar problem with my 06 900. At 6500 rpms it would cut out or sputter but I could pin it and would run strong. Cleaned my exhaust valves and by-passed the exhaust valve solenoid and its fine now. Just took the T out where the solenoid is and plugged the exhaust valve tubes. I think the solenoid was gummed and causing it to sputter. This way the valves open and close smoother.

 

[overkill131313]

I had a similar problem with my 06 900. At 6500 rpms it would cut out or sputter but I could pin it and would run strong. Cleaned my exhaust valves and by-passed the exhaust valve solenoid and its fine now. Just took the T out where the solenoid is and plugged the exhaust valve tubes. I think the solenoid was gummed and causing it to sputter. This way the valves open and close smoother.

so did you plug the hose going to the ex valve or to the solenoid?

 

[sledwrek]

I honestly got back from sicamous yesterday and am having the exact same problem with my machine. It ran fine all day Friday up at blue lake, and then as soon as we left the cabin to head home it was coughing, sputtering and just falling flat on its face. I was at Backus Racing most of the day saturday trying to figure it out and it still isnt fixed. We replaced throttle body boots, fuel filter, set the TPS, tried a different can, cleaned the throttle bodies, checked fuel pressure etc. Finally ran out of time so I came home yesterday. Any info or suggestion would also be appreciated.

 

[900sleddude]

so did you plug the hose going to the ex valve or to the solenoid?

I plugged the exhaust valves tubes together with a 5/16 bolt with the end cut off and left the solenoid tube hanging free/open. With them plugged I believe you get total variable exhaust valves back like the old 800's.

Before I did this I would get a quick bog (on an 06 900rmk) around 6500 rpms while going across an open meadow at 6000ft. It would bog almost everytime at 6500 but a little below or above it was fine. I figured out ( with help from other 900 owners) that is when the ecu tells the solenoid to close which will open the valves. My exhaust valves did need to be cleaned also since I had been using regular Polaris blue oil since I rebuilt my engine for 275 miles. The solenoid also looked like it was getting pretty covered in oil and might not be working as fast as it used to.

 

[900sleddude]

I honestly got back from sicamous yesterday and am having the exact same problem with my machine. It ran fine all day Friday up at blue lake, and then as soon as we left the cabin to head home it was coughing, sputtering and just falling flat on its face. I was at Backus Racing most of the day saturday trying to figure it out and it still isnt fixed. We replaced throttle body boots, fuel filter, set the TPS, tried a different can, cleaned the throttle bodies, checked fuel pressure etc. Finally ran out of time so I came home yesterday. Any info or suggestion would also be appreciated.

The only other thing I can think of is that some guy's have had a plastic elbow come loose in the fuel pick-up/pump assembly inside the tank. As you get lower in fuel it could be sucking in air or something.

 

[overkill131313]

I honestly got back from sicamous yesterday and am having the exact same problem with my machine. It ran fine all day Friday up at blue lake, and then as soon as we left the cabin to head home it was coughing, sputtering and just falling flat on its face. I was at Backus Racing most of the day saturday trying to figure it out and it still isnt fixed. We replaced throttle body boots, fuel filter, set the TPS, tried a different can, cleaned the throttle bodies, checked fuel pressure etc. Finally ran out of time so I came home yesterday. Any info or suggestion would also be appreciated.

that was your first problem! Backus! I worked there last winter and saw way to much `just change parts`and charge to customer! plus they hate to work on 900 and charge for it. plus parts are way cheaper in Vernon at 4 seasons Polaris!

I`m going to do the hose block off for the VES. but first I have to fix the belly pan from a exploding belt. I guess after 1000 miles I need to change it lol. the belt before went for 1500 miles and is now back on the sled since it was my spare lol.

Im going to look at a cracked bellow in the ves. I remember one was getting ugly but didnt have a spare!

 

[overkill131313]

The only other thing I can think of is that some guy's have had a plastic elbow come loose in the fuel pick-up/pump assembly inside the tank. As you get lower in fuel it could be sucking in air or something.

my tank was right full when we left the parking lot and it stumbled at mid throttle all the way up to 5000 feet then worked great all day! then stumbled on the way down lower than 5000 feet.

 

[sledwrek]

Yeah i am starting to think you might be on to something with the exhaust valve thing. I am going to pull them apart tomorrow and see if the bellows are ripped or if the valves are dirty and sticky. If that doesnt help anything i will try bypassing the solenoid i guess.

 

[H2O]

So what did you guy's find out?
Any progress at finding the problem?

 

[overkill131313]

ya dont run av gas lol runs much better on just prem 92 lol it got better as I added more fuel. I put the wrong jerry can in (av gas lol) I guess it made the egt sensor think something different lol. dont ride it any more since the turbo sled is on the back of the truck now lol.

 

[overkill131313]

oh and found a major exhaust leak at donut. it didnt like that smoke under hood!