Trouble Idling When Cold

[musselman]

Musselman, did you bother to replace the cam position sensor, or pressure sensor when all apart? I would like to narrow down the easier fixes 1st since my sled is doing the same as yours. I plan on replacing the TPS since it was known to be bad.

No did not replace any sensors, only swapped the pressure sensors to see if they made a difference but it did not. I'm still running the originals. Should be able to give it a test just after christmas hopefully.

 

[findkeys]

This is the nut I am referring to.

This is the nut I am referring to.

Hey mine seems to have the same issue as yours have tried most things you have with no results Did you ever try adjusting that nut or figure out the issue yet

 

[musselman]

I don't think that nut dose anything actually, more just to hold everything together. I just synced the throttle bodies last night, they were out a bit but seemed to help with the response once they were equalized. The real test will be this weekend, I will compare the fuel mileage to our nytro, last year it was always 15 or 20% better on fuel, I don't think there should be that much difference.

 

[musselman]

 

[sideshowBob]

One of the sleds I ride with is a late model Nytro and it constantly gets better mileage then my Attak...usually better then the 800 and 850 Etecs

 

[renegademan17]

Tore mine apart tonight and going to replace TPS and sync throttle bodies, 3 2 strokers done and now the 4, wish it was as simple as those 2 strokers!

 

[sideshowBob]

Any updates?

 

[musselman]

I do have some updates, have put on just under 1000 km so far so lots of seat time.

1. Cold start up low idle has not been an issue, there have been plenty of -25° starts. It does have a lumpy idle about 15 seconds after it fires but the idle stays up around 2000 rpm instead of falling to 1000, sounds similar to other apexs I have heard.
2. When it's not fully warmed up (light out but not fully hot) the idle will drop if the throttle is messed with, however if it's left alone it will recover on it's own. Once it's hot response is great and no issue with the idle.
3. Fuel mileage seems a bit better, only a couple liters behind the nytro, I ride much harder though so that could be the difference.
4. Top end seems to be better, I was pulling about 10,600 before, now it pulls closer to 11,000, maybe 10,800. Also 180 km/h was easily achievable on a straight trail.
5. The exhaust note at idle seems to be louder, multiple people have commented an asked if I gutted the exhaust but it's still stock. At cruising speed it is quiet though.

All in all it seems to be running great so far, just have to fix my shock wires now

 

[steveg_nh]

Great update!

 

[sideshowBob]

Thanks for update....have a fun safe riding season

 

[TBay Sledhead]

Just completed a valve adjustment on my 06 Attak, starts good idles spot on like it should. 2500 on start up and 1500 when warm steady as a rock. been chasing this for 2 years. Been doing this since approx 20,000km now at 28,000km. Only tried from warm in heated garage so will try outside tomorrow. Supposed to only go to -3c overnight. Need to reset the CO settings back to 0.

 

[steveg_nh]

This is such a great thread, to help others do their own valve adjustments. I likely will do it myself when the time comes.

 

[musselman]

Thanks for the update!! Glad to hear some others had some positive results. I hope to have more seat time by next week, that is if we get any snow!!