pro rmk idle hanging

[rowe]

Did a bunch of work to the sled this fall and its finally back together. When I stop now it wants to idle a bit high and takes a little while for the idle to come down. Sometimes it takes 10 seconds sometimes 20. Its random. Every now and then it will idle down properly when i let off the gas but sometimes it takes a little bit. Usually idles at 2300-2400 before it comes down and does it also sometimes when i start it up after riding. When i used my reverse earlier it idled at 3000ish for a little bit. About 35kms on it since I put it all back together.

It never had this problem when I put it away in the spring.

The only thing I changed motor wise was the fuel filter and reeds. Had valves out to clean but I dont see those causing an idle issue.

Any ideas? Sled runs fine otherwise but the idling is an annoyance.

 

[xc6rider]

Youll want to check for air leaks, around your reed cages, and fuel leaks/seals from fuel filter install. And check/set TPS to specs.

 

[rowe]

If it was an air leak wouldn't it constantly idle high? I had already checked the fuel filter lines for leaks after running the sled.

 

[Ski-Dont89]

mine started doing the same thing last year. while its idling high if you cycle the kill switch super fast it will stay running and return to normal idle. so this tells me its definitely something electrical. tps hanging or something? weird

 

[xc6rider]

If it was an air leak wouldn't it constantly idle high? I had already checked the fuel filter lines for leaks after running the sled.

Depends on how bad of a leak. It could just be kind of a puffing leak, if their even is one. Did throttle bodies get seated/sealed correctly?

No way you damaged a reed on install?

Ex valves get sealed up tight?

Just tryin to throw you some things to look for...

 

[rowe]

Made sure to get everything seated good yup everything was tight. Didn't damage the new reeds. New exhaust valve gaskets and was all torqued to spec. I'm getting a fix kit installed this weekend and also going to get the tps adjusted and then go from there i guess

 

[rowe]

Have to move the sled this week sometime. I will try the kill switch thing and see if it does that

 

[sartysrnr]

What fuel filter did you use?I read a lot of problems with spi filter lines kinking .Sure it not kinked and leaning it out?Just a thought...

 

[rowe]

The filter is spi or spx. I cant recall for sure. The kind royal distributing stocks. Never seen any kinks in the filter line but i will double check that too. I snugged up the hose clamps a little more on the throttle body boot earlier and got a look at everything (without taking everything apart again mind you) and everything looked good. Throttle cable play is good. I did the kill switch thing that was mentioned. Did it while it was idling high and it made no difference. And i did it while it was at the proper idle and the rpms would shoot up to 2200-2400 for a second or two then come back down.

Thanks for the suggestions so far.

 

[sartysrnr]

Well those being the only 2 things you did i would swap the old filter back first if its not destroyed and then check for air leaks around the reed gaskest or intake boots.Did you go over the intake boots good?The rubber tend to lift off the backing at the bottom sometimes hard to notice.

 

[rowe]

The old filter is long gone. I looked the boot over the best i could and didn't see anything. I think if the tps adjustment doesn't fix it i will pull the air box again and get a better look at the throttle body and boot.

 

[greasemonkey3406]

I'll have a good look at everything when it's all apart.

 

[mtncat1]

check it for vacuum leaks , the easiest ways to cheack are 1 with a spray bottle full of water spray all around the engine base gasket area throttle body boots crank seal etc. starting fluid will also work well , any change in the idle speed will indicate a leak, if you don't find any thing there , pull the air box out and inspect the throttle plates for closing . i doubt a fuel filter could cause the issue but it is possisble. good luck and don't ride it until you nail down your issue . serius engine damage my occur. good luck

 

[greasemonkey3406]

One thing you can check also is the paint marks on the bolts that hold the tps in place. Maybe they were bumped and the adjustment went out just a tad?

 

[rowe]

One tps screw is off the mark a tad. Fuel lines good, no kinks. Looked at the boot more and no signs of not seating correctly. Haven't tried spraying anything yet

 

[greasemonkey3406]

Ok, I worked on this thing for a bit. It idled high when I first looked at it.
I installed the SSI durability kit and everything went well.
I reset the tps. Base was at 0.680 and set it to 0.700. Idle was at 0.922 and set it to 0.930. Fired the sled up today and still idles high. 2200-2300. After it warms up a bit and I put it in reverse it idles fine, then put it back in forward and then idles back up to 2200. Throttle cable adjustment is good. Kept the meter on the tps wiring and even when its idling high, the voltage reads 0.930. I can unplug the temp sensor on the airbox and it will idle down fine. Also, if I push on the oil pump arm with a long screwdriver, it will idle down but the tps voltage will drop also.
Wondering if I should try another air box sensor. Was also going to remove the tank and airbox and check to see if the oil pump linkage is hanging up the idle. If I go this route, I will re check the boots and check for air leaks. Any suggestions out there?

 

[kanedog]

Why not adjust the idle to a little less if u have checked everything else?
It's on the mag side of the throttle bodies and it has a tiny Allen key hole and a tiny lock nut. Back off lock nut and adjust set screw for nice idle action. Tighten lock nut while holding Allen wrench. Ride.

 

[greasemonkey3406]

I just wanted to exhaust all options before I adjusted the idle anymore. .930 is right on the spec so if everything else is good I'll go that route. If the idle is slightly below spec would it affect the top end?

 

[kanedog]

. If the idle is slightly below spec would it affect the top end?

I don't know the answer to that question.

 

[greasemonkey3406]

Had everything off: fuel tank, air box, throttle bodies, boots and reeds and everything looks great. Everything was tight in the proper place. Checked the oil pump linkage and it is not hanging up anything. I reinstalled the reeds and boots and torqued the bolts to 9 ft/lbs. Reinstalled throttle bodies as well. The next thing I will check is to turn the idle screw back out and get the tps back at its baseline and check to see if the throttle plates are closed.
If the plates are not closed all the way, do I need to mess with the synchronization screw? I read that you back it out all of the way so that it does not touch the plate and then reset the tps baseline to 0.700 then turn the screw back in until it just changes the voltage and back it out again until it reads 0.700.
Anyone else have to do this for a high idle issue and did it cure the problem?