help: 06 M7 randomly died (fuel, ignition, wiring ?'s)

[catman_88]

update

so my sled will run for a good 10 seconds but will not let me rev more then 3800. yes throttel senser right? well my sled is giving me two flashes again and stays running after so it has to be the water temp for me.

 

[Spook]

Problem: Riding down a trail, sled suddenly dies. I figure I accidently hit the kill switch which is exactly what it felt like. Nope, kill switch is up, key is on. Over the next 30 minutes I fiddle with connections pop the switch and key a bunch and manage to get it to randomly fire up just to have it almost immediately turn off again. Had to tow it home. Once home and playing with things I couldn't even get the random fire up anymore.

At this point I haven't had the chance to go through spark and fuel testing, but will soon.

I read up and find there are many electrical problems with the M7's. Tail light wiring, kill switch, tors, main harness. Are there any others? My friend rides an M7 as well so I can probably swap some parts over and determine which items are toast, but I can probably also do that with a tester.

At this point I've disconnected all the handlebar accessories and switches to negate them as the problem. I don't have a service manual though, so it's hard to figure out all the details. Is the kill switch circuit normally open when the sled is running, or closed? I figured open and therefore disconnecting the kill switch harness should allow the sled to run if the switch has a short. How about the key?

Which connector on the sled goes to the stator? Is it the yellow one coming up near the oil reservoir? Which connector disconnects the throttle override switch? Is it the one on the end of the throttle body near the oil reservoir? Is this also normally open?

Today or tomorrow I'll start actually diagnosing it for spark and fuel, but this info will help going forward.

What is the failure rate on fuel pumps, computer, and ignition components on these sleds? Any other ideas on what could be causing the problem? The sled was running fine and then this just seemed to randomly happen. At first I thought it was related to my chest bumping the handlebars.... but it doesn't look that way. The sled has ran great all season, I had a couple instances of some breakup and bogging earlier in the year but haven't experienced it lately.

As you can see I'm new to this sled, gonna order a service manual unless someone knows of a pdf download somewhere?

Thanks for any help!

I haven't read all the post's.. But I had serious problems with mine. I thought it was electic. Changed everything out. ECM.total harness. stator. I mean all of it. Come to find out it was my fuel pump. It would build enough PSI after pulling on it that it would fire and die.

Put a fuel PSI guage on it and pull it over. Just a thought. Good luck.

 

[WyoBoy1000]

Do you have any mods?

If its over fueling like that then the first thing would be to check Fuel Pressure. F/P gauges can be off, I had one go 2lb to 15lbs off. If the fuel pressure is weak, get a 12v source and hook up to the fuel pump wire but hook it up backwards, it will run the pump backward and might clean it out if something is restricting it, then hook it up and try it again. If you did it right you could pull the injectors and hold them in the fuel rail and pull it over, you might see one stuck or dribbling. If the sled will run around 4000 rpm and shut down it is related to the throttle safety switch, you may have a short somewhere else causing it to kick in. If you could find the wire going into the ecu that works with that switch and pull it out it should eliminate that completely. disconnect the brake wires down by the brake rotor to cut that out to. disconnect the hood wiring. There is also another ground that bolts somewhere around the recoil I think, not sure on the m7. Put new plugs in, drain all the gas and put some new in. check to make sure the wires going into the injectors are not broke, they will break inside the insulation some times. Try a pipe temp sensor.

 

[catman_88]

I did check all my wires and they seem to be fine. but now my sled will rev over 4600 and stay running for a good 30 seconds and its giving me all different kinds of codes. its better sines i found that peace of plastic in my reeds and my reeds looked fine no cracks nothing visible.

 

[509kid]

so any luck fellas???

 

[WyoBoy1000]

What codes. I would talk to a dealer about the codes they might know how to reset the ecu(clear the codes).

 

[catman_88]

ok well now if you dont rev it up it never gave me any codes, it will idle for a long time. it sat and ran for 1: 30 seconds then i rev it up and as soon as it hit 4500rpm it dies so i tried to ajust my throttle cable then it would not start and i lost spark then i gave up on it last night. I was playing with the cable after school ajusting it very slowly and often but still no spark. thats when i noticed my black/yellow wire was burt up at the front going in to the ECU. That wire leds down to my stator and i tested for continuity and it was good. but it might have burt though another wire some were alse in the harrins.

the wired part is that its running alot beter sinse i found that peace of plastic in my reeds.

has any one alse figured any thing?
I all so have my sled doing this on video and the code but it looks like a wire shorting out when the engina light comes on. I'm so lost

 

[catman_88]

how do i set my throttle cable? like how much play should i have?

 

[WyoBoy1000]

I just set mine so when the throttle is pinned there is no slack, if the throttle is not pressed down at all and there is slack then it should not cause any problems. Maybe something is messed up with the TPS but that is something you don't want to mess with, you have to have a special tool to set it. If you have a burnt wires I would just put in a new wiring harness, I know its not cheap but you could spend a lot of time trying to figure it out and come up with nothing, and loose a lot of ride time.

 

[catman_88]

i did what you said to set it and still nothing. no spark so i ordered a new harris i got 10% off to came out to be 300. be here friday if not that then i dont know. but its like +5 all day! no! every body is so happy.

 

[kartorium]

I'm moving to the wiring harness on mine. Is there a way to disconnect the wires going over to the clutch and then down underneath? I don't see a connector for the set.

No solution yet.

 

[kartorium]

This afternoon I had full nice spark at times for 10+pulls at a time. Got the sled to fire, runs for a few seconds then turns off. Then I go to check the spark and there's nothing or its very weak.

One of the only thing I haven't disconnected while testing for spark is the harness that goes to the box with the clear cover that is right by the spark plugs. I also haven't tried unplugging the wire that goes down by the secondary clutch. I couldn't get the TPS sensor unplugged either.

When people say they are replacing the main harness, are the talking about the main engine harness, or the main harness that goes to the ecu and connects into everything else including the main engine harness?

So to recap:

Can a coil be intermittent like this?
Can a stator be intermittent like this?

If not, the only thing left is the wire harness as everything else has been disconnected or accounted for as not creating weak/intermittent spark. At least that's where I'm at. Thanks for any help... I feel like I'm getting closer. My goal is to have the problem identified by the end of this weekend.

 

[doornenbal]

my new harness should be installed today!! I will post as soon as i know

 

[kartorium]

I took my harness off my sled, put it on the other M7. It tried to fire twice, then fired and ran for a few seconds, then shut itself off. I pulled it many times after that and couldn't get it to fire.

Couple items that are questionable, and I want your opinions on. (possible variables)

-I didn't connect the harness ground to the normal ground location, I put it under one of the screws that goes through the heatsheild on the main steernig hoop. (ease of assembly). I highly doubt this could cause a problem.... but....

-I didn't connect the speedo wires. In order to get the harness off my sled I simply cut the harness going down to the diamond drive. Think this could cause problems?

-I didn't hook up any of the handlebar accessories, speedo, taillight, etc on his sled to my harness. I did this to decrease variables, let me know if for some reason it could have added one.

After that I hooked the original harness on that sled back up, it fired twice, then on the third pull it fired and ran like it should. I'm guessing there was probably some fuel in the cylinder from the previous pulls using my harness.

So, I'm about to buy a new harness. I couldn't figure an easy way to get the harness off the good sled without cutting that speedo wire, so I decided taking the harness from the bad sled and putting it on the good sled would be the cleaner option.

Any last thoughts before I order another harness?

 

[doornenbal]

Put in a new harness in mine, fired up first pull

 

[catman_88]

it was the main wire harrnis

 

[kartorium]

Well, almost 3 weeks ago now I blew out my knee. I just now got a chance to put the new main harness on. Didn't start right away, swapped the plugs and checked all the connections and she started right up. So far it is running great, no CEL's and seems to be revving smoothly without misses.

So, if you seem to be having phantom spark issues, take the main harness into serious consideration.

 

[Blk88GT]

Can you diagnose where on the harness the failure occurred?

 

[kartorium]

I'll start going through it here within the next couple days. The initial visual inspection didn't show any significant damage. I found one wire that was a bit white, like it had been rubbing on something, but it wasn't through to the conductor.

Regardless if I find a problem with it or not, if for some reason anyone wants this harness, shoot me a PM.

 

[509kid]

i had the same problem, i ripped apart the plug end at the ecu... you can not see it by just looking at it, it was all melted on the inside for sure. i plugd a new harness in and it fired immediately and runs great.