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

[apex55]

Tbay Sledhead I was reading on the IAC and they say that you have to re syc the carbs if you remove the IAC,

Did you re syc the carbs after you installed the IAC from the other sled?

Do you have to re syc the carbs after you remove the IAC?

I had a Yammi mechanic resync the injectors. Not sure how he did it. I didn't replace the IAC, but he said it needed to be done and the sled ran much better after.
Culley's Ranch was the dealer who did it. I don't think they are in business anymore. They used to be big in grass drags.

 

[TBay Sledhead]

Well I swapped out the temp sending unit. sled still stalls. I guess I'm going to have to figure out how to sync the throttle bodies.

 

[tomanytoyz]

Dam ok let us know !

 

[WinderFab]

Tbay Sledhead how's your cold idle when you first start your sled?

Over the weekend I was riding with a few other apex's which don't have this problem and we all noticed that my sled does not sound the same on cold starts as the other apex's,

Sled starts fine every time, idles at 2000 when it's cold at start up than with in a few seconds the rpm's start to fluctuate up and down 1500 to 2000, with out touching the throttle the motor does not sound like it's running right, I'm not a motor wizard so it's hard to explain but sounds like it's stumbling along like it's being starved from something, as soon as I touch the throttle even just enough to raise the rpm's a hair the sled sounds good the way it's supposed to,
After riding all weekend with others apex 's mine sounds way off,

Does the IAC also control cold start ups?

 

[biffdotorg]

Tbay Sledhead I was reading on the IAC and they say that you have to re syc the carbs if you remove the IAC,

Did you re syc the carbs after you installed the IAC from the other sled?

Do you have to re syc the carbs after you remove the IAC?

I had a Yammi mechanic resync the injectors. Not sure how he did it. I didn't replace the IAC, but he said it needed to be done and the sled ran much better after.
Culley's Ranch was the dealer who did it. I don't think they are in business anymore. They used to be big in grass drags.

I went in and talked to my local Yamaha mech about cleaning my IAC and syncing my injectors. He looked at me like nobody had ever had this done before. I really don't know what to do other than I'm not going to try doing this myself.

I have no issues dropping the skid, and ripping the front end apart but going into the fuel system etc no way. I may cart it in there at the end of the season and just request it. It's running fine now but losing MPG for sure.

 

[02xtreme]

Here's what I'm finding lately. If its colder than -10 Celsius, its idles near perfect all day, unless I come to a stop and let it idle for more than say 2 min, then it drops to 1000 RPM. If its less than -5 Celsius it idles low all day long, still starts and runs fine, just idles crappy.

Is there some sort of atmospheric pressure sensor or something???

 

[WinderFab]

Mine does it no matter the temp...

 

[yamyfreak]

I would check for a vacuum leak on your throttle bodies. this will cause an erratic idle and stall. I mean the vacuum lines, not necessarily the boots on the throttle bodies.

 

[WinderFab]

Thanks yamyfreak I will try that,
I did some work on the sled the last week or so that fellow tier's have suggested, cleaned the IAC, checked the ground blocks, checked sensors, etc, TPS sensor test was also good, all with no luck,
Last time I went for a ride I think it's getting worse, it stalls a lot quicker now when I come to a stop and let go of the throttle so it might just be a vac leak some where, maybe when I'm under there moving things around I'm making things worse,
I'm going to go over every hose as good as I can and I will post back, if I have no luck it's going in on Tuesday to a very reputable dealer close to me,

 

[biffdotorg]

I was stalling more as well till the last 100 miles. Now it is backfiring. Time for exhaust donuts!

That would be a safe assumption don't you suppose?

 

[black knight]

donuts would be my guess
for anybody that wants to check for a vacum leak through the IAC
pull the air box off and the 3/4 inch hose that gose from the air box to the
IAC blow in it or a wet rag and the nozzel of some light compressed air to pressurize,
do it with the throttle closed and the throttle open.
Throttle open you will hear the air going through. throttle closed you might find a leak
i bumped the little screw on the butterfys half turn to open them a little hair
and it is holding idle a little better now
when i start mine it idels up fine then about 10 sec in to warm up it starts to bog down
until i give it a little throttle until warmed up then its fine
then similar symptoms as the rest of you on warm days
My TPS from the dash diagnostics is 16 and a little pressure on the throttle gets me 17
i wondering if it needs to be bumped down to 15 by moving the TPS to give that reading.makeing the fule leanner at idle

 

[Clubin]

Mine was doing this. I cleaned the iac valve but that wasn't the problem. My problem was the rubber boots that connect the air box to the throttle bodies! They were on but not all the way over the bump. It was a bit if a bugger to get into place. But once it was I set my idle using the iac and haven't had a problem in 800 miles now.

 

[black knight]

yah getting the air box on rite is a pain. the last boot on the cluch side hits the iac and you think you have it on but the bottom is not seated.
for me anyway. its hard to see in there.
I know in the past i haven't had it on correctly. just by looking at the boots ofter taking it off you could see boots weren't all creased the same from the lip on the throttle body.

 

[thor452]

Tbay Sledhead how's your cold idle when you first start your sled?

Over the weekend I was riding with a few other apex's which don't have this problem and we all noticed that my sled does not sound the same on cold starts as the other apex's,

Sled starts fine every time, idles at 2000 when it's cold at start up than with in a few seconds the rpm's start to fluctuate up and down 1500 to 2000, with out touching the throttle the motor does not sound like it's running right, I'm not a motor wizard so it's hard to explain but sounds like it's stumbling along like it's being starved from something, as soon as I touch the throttle even just enough to raise the rpm's a hair the sled sounds good the way it's supposed to,
After riding all weekend with others apex 's mine sounds way off,

Does the IAC also control cold start ups?

I am almost 100% certian that your iratic iddle is due to the bad tps that yamaha had for awhile and they did a recall on the sport bikes but not on the sleds was coverd in the form over a year ago quite extensively and if you have an 06 or 07 sled you may just want to replace that even if you think it is okay.

Also the rest of you look very closely at the vacume line that feeds the fuel regulator it has been found to have a hole that can only be seen when the line is removed.

hope it helps if not im out of sugestions sorry.

 

[4Fighter]

I've noticed another problem. Not only does it stall when you slow down, or come to a stop. I was blasting down a straight-away and it stalled-out. It just quit, and coasted to a stop. Outside temp was probably 5*F It took a few cranks to get it going again. Did it twice in the same weekend. Second time it pulled that crap, it was -10*F or so. I've gotten so accustomed to it that I feather the throttle when I'm slowing down.

So here I am getting ready to price out sensors, and other stuff that MIGHT be the problem. I'll be damned if I'm ripping that exhaust apart AGAIN after 500 miles of installing new donuts, and header-pipes. I for one would appreciate a straight answer from the people who designed the system. Until then, I'll try 'nate's' suggestion and do the things that most likely won't cost too much until someone gets a definite handle on the problem.