First ride out with problems( please help)

[W A O]

Went out today for the first time this year.Sled ran great for the first three hours,Ran some 4 to 5 sec hills not to big but enough to see my RPMs. 7950-7980 was told 8000 was my target so clutching looks good.Just had a pipe put on and milled the head 10 thousanths.
After about three hours of good rideing I got a top end bog.
Sled runs good 6000 rpms and lower but if you pin it bog bog bog.
Checked plugs and clutch side looked good but brake side looked a little grey. So I limped back to the trailer and came home.Piston wash looks good Checked compresion and 120# in each so no problems from lean but why only one side,and why the bog.
I have a 06 m7 it has as follows HPS can, speedwerx air horn, frogskinz on intake box by air horn,venting and clutching, it ran great for two years like this.
This year added the speedwerx fat daddy pipe and milled the head to get just a little more.
No box was told I didnt need one
Did find the tube on ECU was mabey cloged, put new plugs in it and on the stand it runs fine so why? Can you help, just dont want to have bigger problems, or deal with that dam bog.
Thanks for you help.

SEAN

 

[M8 Rider]

2006 m7 efi

The check engine light is not on. Does the light need to be on for the EFI scanner to read a code like a car? Everything else checks out good. The snowmobile ran great at first and then the problem occured. Could the throttle safety switches be at fault? Thank you for the help!

Mike

 

[89sandman]

power valves??? know mine open at 6,500...

 

[thekrust]

X 2 on the power valves... Make sure they are not stuck shut.

 

[W A O]

Power valves

power valves??? know mine open at 6,500...

I took them out today, Clutch side looked ok not to bad and the brake side was dirtyer then the other. The cables seemed to be the same lenth and moved well the brake side valve was sort of draging. Hope this fixes the problem. Could not find anything that was a (ok that was the problem) sort of thing.
Thanks for the help, the more I learn about my sled the more I learn that I dont know much.

 

[M8 Rider]

First Ride Problems

We went riding today and tried several things. The problem still exists. What happens intermittantly is when throttle is held wide open it feels like a rev-limmiter is activated. This problem happens intermittantly and when it does it runs great at 1/2 throttle or less. The only modifications to the 06 m7 are HPS silencer,Speedwerx single pipe,and 010 milled head. The silencer has been on since new. The problem at hand may not be related to modifications. Seems like ignition but may be fuel. Any suggestions will be appreciated! Thank you for your help!

 

[Rucky]

We went riding today and tried several things. The problem still exists. What happens intermittantly is when throttle is held wide open it feels like a rev-limmiter is activated. This problem happens intermittantly and when it does it runs great at 1/2 throttle or less. The only modifications to the 06 m7 are HPS silencer,Speedwerx single pipe,and 010 milled head. The silencer has been on since new. The problem at hand may not be related to modifications. Seems like ignition but may be fuel. Any suggestions will be appreciated! Thank you for your help!

That sounds like the Detonation sensor. I have that happen with my M8 the odd time. It flashes OCTANE on my gauge. Shut the sled off and it resets itself. That's just in my case anyway.

 

[Burn Down]

No detonation sensor on the m7. Do you have fuel pressure gauge? Stick the gauge in line after the fuel pump, should be running around 47 ish if memory serves. Whack the throttle and make sure its keeping fuel pressure. Maybe check your sump in your fuel tank make sure the 3 screens are clean fuel lines aren't clogged. If that all looks ok maybe you got some electrical problems, throttle position sensor?

 

[sledbasher M7]

acting up

make sure your tail light wires are not rubbed throught.This will cause a lack of power for the entire sled.This happened to a bud of mine.Would rev up good then lay right down.Shut it off and it would work good for a litle bit.Tell tail sign is no or poor headlights/tail light.Just a thought.

 

[W A O]

Fuel press

No detonation sensor on the m7. Do you have fuel pressure gauge? Stick the gauge in line after the fuel pump, should be running around 47 ish if memory serves. Whack the throttle and make sure its keeping fuel pressure. Maybe check your sump in your fuel tank make sure the 3 screens are clean fuel lines aren't clogged. If that all looks ok maybe you got some electrical problems, throttle position sensor?

Checked mine and it holds good at 43 psi, should be good? Or what should it be.

 

[9.90 Camaro]

Next time out unplug the 10% ethonal plug by your computer its a single wire bullet plug in when unpluged it richens the fuel mixture up and see if that helps I have twins on my M7 05 and it needs a fuel controller I add fuel in the low and high and take some away in the mid. I also lost the stator in mine and it acted way stupid one ride felt like I ran out of gas dumped my extra gas in and when got home to unload out of trailer wouldnt start pulled it in the shop with 4wheeler 10 min later it started run it around the yard ran fine put it back in shop next weekend fired it up ran across shop opened the door and grabed throttle to run out side and it died never to start again tested stator was bad put new one in and has ran great ever since.

 

[Burn Down]

Checked mine and it holds good at 43 psi, should be good? Or what should it be.

That should be good a little lean but ok, sounds like you have a electrical problem.

 

[spomey]

I would remove the ECU from the machine and do everything I could to make sure the hose isnt clogged. My bet is it has a small "drip" of water that wont allow the pressure changes due to altitude be read and that is the cause of your troubles.

Was the poor performance after a few hrs of run time at a different altitude?

I was amazed at the difference on a M1000 after I found the problem.

 

[W A O]

Ecu tube

I checked the clear tube on the ecu and it looks clear but when i pulled it all the way out it had some fuz from my belt explosion last year on the end,that stuf goes every where.Cleaned the fuz off and cleaned my power valves and went out on friday and still had the problem. Altitude change may have been 80 feet but i ran on friday every where that I ran on 12-26-09 when it ran good for 20 miles befor the problem started
thanks for the info to check its worth the try

 

[W A O]

Update on problems

Whated to start out by saying thanks to everyone that gave some help or tried to it all helps to think in a different direction.

So your not going to belive this one, Took my sled to the dealer to get the ecu,stator,and so on checked, all good. Read a post on another problem and some one asked several question to help out someone eles.
One of the questions was is your exaust clogged, Bingo my three four year old can with 1256 miles has come apart inside and is moveing around, thus the hit or miss performance.
I dont understand why but it did, I will call HPS tomorrow and see if they will help me out some way?
Man what a pain but I am so glad to know atleast what it is, will let you know what they say.

 

[Burn Down]

Thats great you found it but sucks it was the can causing all your headaches. Anyhoo have fun riding.

 

[W A O]

Can

Hey I called HPS today and the guy was real good to me explained his can to me and why its different and is sending me a new one.
I think he has done his part and has treated me right.
Opening in the can was not very big after all that stuff came apart, just like if the power valves did not open,this should fix me up.
Now all I need is some SNOW!!! thanks for your help

 

[AMP]

Try A Voltage regulator... Seen a half dozen or so do this same thing top end miss !