07 apex rpm's very low and stalls when warm on idle

[02xtreme]

Extreme keep us posted if your fix works for you. I have the same cold start sympton as you. I adjusted my co from -5 to -10 seems a little better in that the rpm does not fall as low but it still drops from 2000 ish to 1500 with a rough idle sound then recovers but almost surges a bit. Ive been lucky not having the issues so much warm. Only on cold start when the warm up light is on. Even when the sled has been parked for a hour it starts up and idles great at 2000 rpm nice and crisp but with no warm light on. start it from cold with warm up light on will stumble like i mentioned.

My cold start stumble is still there, however, my idle once warm throughout the duration of my ride is now staying at 1500 ever since I set CO to -10. Last night I let it idle for about 5 min and blipped the throttle the entire time and each time it came back and settled steady at 1500. I do find this problem was worse when the temp was warmer than -5 Celcius and it has been much colder than this lately - so I'm hoping its not the cold weather and in fact I have found the issue. Now I just need to figure out the cold start stumble. Do you guys run the CR10EK's out of curiousity?? That's what I'm running and I'm wondering if they may be the issue??

 

[TBay Sledhead]

I'm running 9's

 

[WinderFab]

I've heard people having problems staring there sled in extreme cold when they are using cr10ek's

 

[black knight]

9 's here

 

[Grunter]

Wow - my sled has been doing this for about a year now..
After the initial start it did the hoeky idle after about 10-15 seconds - same as many of you guys mentioned on here.
It has 7600 miles on the odometer...
I've checked quite a few things and figured maybe the TPS as some have suggested...
My 5.0 1990 five liter mustang has had similar issues that I solved with a new TPS..
There's a bit of grease in there that could dry up and affect how it returns to zero positon or not etc..
But on the five liter this affected the voltage that the ECU receives to calibrate the injectors..(pulse width & pulse length)

But decided to try the CO adjustment as suggested on here before mucking with the TPS!
Mine was at 15 because of the Ulmer Racing air box mod and a few others..
I backed it down to 10 then 8 now..

It's not perfect - but much better!! It's still very responsive(maybe a tad more even)

Don's get the hooky idle anymore..
My idle actually went up - so I had to reduce it to 1500 from about 17-1800rpm..
Now when I blip the throttle - it drops to 12-1300 not 8-900rpm like it used to..
It then recovers and goes back to 1500rpm ;-))

So I'll try it this weekend and report back on it's behaviour!!

Thanks guys!

 

[JROCK]

Stock 9's replaced 2500km ago.

 

[WinderFab]

Thanks 02xtreme for the info,
This morning I set my CO adjustment to -5 on all four, just got back from a good days ride and my idle is 1500-1600, tap the throttle revs up and goes back to 1500-1600 going to go riding again tomorrow I'll report back,

If this works thanks again 02xtreme...

 

[tomanytoyz]

This is great for all you guys having this issue !

I believe that the CO settings is just for idle and 1/4 throttle,you should have no problems mid to top?

I have been running CR9EK plugs for quite sometime.they are just like the 10's but a warmer plug.

 

[TBay Sledhead]

The belt cover on my attak actually calls for 8's. I never noticed that until this year.

 

[tomanytoyz]

The belt cover on my attak actually calls for 8's. I never noticed that until this year.

Really? i know that some sleds sold in Canada have a few differences ,-suspension springs - speedo km -but had no idea that sparkplug type for the engine would be different .

Maybe cause of the temperatures up there?

I will have to go take a look at mine ,i believe stock here is 9EB but i run 9EK with the proper gap of course .

 

[WinderFab]

My cover calls for CR9EB

Another 340k today, 700k and sled is running perfect since the CO adjustment, I might raise the CO a bit my rpms are at a steady 1600 or a touch above,

I remember adjusting the CO when the sled was new there was a slight stumble sometimes so I put them at +5 for all four cylinders and that took care of it, so far the last two days motor is running crisp again, I was getting a slight pop sound coming from the airbox area (intake) on idle, that is gone, I guess running rich it will pop a bit,

Thanks again everyone and 02xtreme, so far so good...

 

[TBay Sledhead]

I don't think that it is temp related because the problem would go away when the outdoor temp warmed up and I still had the problem when in the Gaspesie, which was much warmer than it was here.

 

[black knight]

ok ,so i played with the Co settings today as per the TY Tec section and others have mentioned above

I adjusted the Co to -10 on all for holes from cold before i even started it
It was about -10C temp when doing. i started it and it sill had a little cold start rumbble
but not as bad as usual.
Warmed it up and blipped, slapped whacked the throttles 100 times and all i could get it to do was drop to about 1300rpm but it would quickly find its way back to 1500rpm.(used to drop to 900-1000rpm)
Rode it around the back forty for half an hour and i couldn't get the idle to drop like
it normally dose. it always comes back to 1500rpm.(it was kind of weird as i've had this idle problem for almost 20,000km Theres 29,000km on it now)
so i bumped the Co settings to -12 on all 4 holes and that raised the idle to 1600-1800rpm
put 100km on it making many many stops wacking the throttle trying to get it to drop.
It was like it was 20,000km ago.Very solid, even taking it up a steep hill real slow and honking on it and letting off at top,like when you load it into a truck or trailer, and it was solid.
Also now when turning the IAC nob on the side of the IAC the idle actually went up and down like its suppose to.
I think my fuel milage may be a little down but i would expect since i technically rich end the fuel.
question is as these get more k on them is this the fix or are we covering something else up.
I'm pretty happy with results i got today, like its the way it was back before it started.
I am going to bump it back down to -10 next ride and run it good just to see what i can get for a consistant idle then do the same thing at -8 setting as well as playing with the IAC adjuster.
I will report back on any other findings
also report on milage

cheers

 

[WinderFab]

black knight for my sled that was the fix, I don't think its covering up another problem, like I said above when the sled was new it had a slight stumble when I hit the throttle fast so I raised the CO and it was gone, about 10 000km later it started idling low, did about another 7000km like that and never thought to lower the CO in till I took 02xtreme advise and it's back to normal again,

I guess it takes 10 000km to get thing loose in there lol,

I adjusted the CO again this morning to 0 because my idle was at 1600 or a touch higher and now it's at 1500, I think the CO was at 0 when I first adjusted the CO back in 07,

Did just over 1000km the last 3 days and sled is running awesome just like the trails here have been

 

[Trailblazergt]

Wow this is the first I've seen this topic and it describes to a T what I am experiencing with my sled for the last couple years, never knew what it was but once she got about a half hour into a ride it would not stall at stop signs anymore, I guess I got used to it and learned to ride with it but it was always bugging me though 'cause it never did it when it was new. I have read all 7 pages on this subject and I would like to try the CO adjustment however I didn't read anywhere what it is or how to adjust it, could someone enlighten me.

Thanks