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08 High Idle Problem

MWGB

Member
My brand new, 5 days old 2008 Road King Classic is plagued with an intermittent high idle. It has happened twice. Each time was after a 15-20 minute ride and a cool down period of 5-20 minutes. I'd guess about 1800-2000 RPM, but without a tach it is hard to tell. With my son on the back, it will do 15 mph at idle in first gear and almost 30 in second. All with no throttle twist. I can get it to go back to near normal by un-rolling the throttle past the neutral point. Let it go and it's back to high idle!

I took it to the dealer after the first event and since it wasn't happening at the time, nothing was done. They did take the time to take it inside the shop and check for any error codes. I don't really feel they were blowing me off; the guy took the time to discuss it with me even though they were buried with other work. Of course, with a 3 day old bike, I kinda expect them to pay attention.

I'd rather be keyboarding about how much I enjoy the machine, and I really do. But tomorrow, I'm taking it in and leaving it there. If they say they can't duplicate the problem and left it alone, then I'll leave it there until someone (dealer or HD mothership) does something to fix it. A shrug of the shoulders won't work.

I suspect either a squirrelly electronic throttle in the handlebar or a squirrelly temperature sensor on the engine. Anybody seen this symptom on a 2008 with the electronic twist grip? I searched the HDtalking archives, but didn't find anything about 2008 problems. With this post, I have at least organized my thoughts for the visit to the dealer.

Any ideers out there?
 
When you shut it off, use the ignition switch, not the kill switch and keep your hand off the throttle. Also let it idle down before turning it off.

I bet you wish you had an 07 now!:D

PS...you're not alone with this problem, many other 08's are doing it.

Congrats on the new bike.:cheers

Here's the DTC error codes for that bike if you want to check them.

08 DTC Codes - Harley Davidson Community
 
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MWGB,
I have a 08 Street Glide.

I had a few occasions where my bike would idle high when I would come to a stop and did the same thing you did by turning the throttle past neutral "roll off" to bring it down but it would climb back up.

The 08 has Electronic Throttle Control (ETC)

I started to watch what I was doing that might be causing this to happen.
If you flip the Run/Off switch before the bike is completely idled down it will keep in memory the higher idle.

At times I would turn on the ignition switch and back the bike out of the garage. When doing so I would slightly turn the throttle.
There were also times when I would ride up to the garage and turn the bike off by the switch but leave the ignition switch on because a song was playing on the radio or I used the headlight to see the key lock on the door. After opening up the door I would push the bike in.
Once again in moving the bike around I could be twisting the throttle when the bike was not running but the ignition switch is on.

I now leave the ignition switch off until I am ready to start the bike and after I have moved it around.

I have not been having any problems since.

Something else to be aware of that my 08 FLHX has that you may also have is Engine Idle Temperature Management System.

If you are twisting the throttle forward (roll-off) for 3 seconds or longer it could be activating this.
I did this while going down the road and it will change it while running.

This is what my book says:
For those riders who frequently find themselves in riding conditions where the vehicle is subjected to prolonged idle conditions or traffic congestion, the motorcycle is equipped with an (EITMS) to provide limited cooling of the rear cylinder.

When the engine is in EITMS operation, you may notice a difference in idle cadence. Additionally, there may be a unique exhaust odor. These are both considered to be normal conditions.

Vehicles are delivered from the factory with EITMS disabled. EITMS can be enabled or disabled by the rider using the following procedure.

1. Turn the ignition switch to the ON position (do not start the motorcycle)

2. Push the throttle to roll-off position and hold.

3. After approximately 3 seconds, the cruise indicator lamp will either flash green (EITMS enabled) or red (EITMS disabled).

4. Repeat the procedure as needed to enable or disable EITMS.
 
HMMMM!!! I think you guys are on to something!
I do recall flipping off the run/off switch on the handle bar as I roll into the garage so as to minimize the noise into the house.

I'll give it a try. The service manual gives a procedure for calibrating a new ETC by cycling thru the ignition switch 4 times while the run/stop switch is left in the run position. I'll do this and then follow up with the proper shut down sequence.

If the helicopters I work on did this, it would be a REALLY BIG PROBLEM. They like to run at 100% RPM, not 102% and not 98%. HD better figure this out before they put in a turbine engine!

Thanks for ya'lls advice. I bet it works.

And BTW Glider, if you weren't so far above the Mason-Dixon line, I might be driving a 2007 RKC. With beaucoup chrome!
 
Here's that procedure you refer to if anybody needs it, it is mainly for recalibrating the system when a new twist grip sensor or ECM is replaced.
Whenever a new twist grip sensor (or ECM) is installed, place the engine run/stop switch in the RUN position and turn the ignition/light keyswitch to IGNITION and then back to OFF four times (without starting engine). Allow at least three seconds to elapse between ignition cycles. As the ECM uses the first four ignition cycles to establish the optimum idle speed, there may be initial performance problems if the procedure is not performed, such as high idle or hesitation when the throttle is opened.
 
Problem solved!
On the first start today, it idled high again. I went thru the ETC reset procedure and now it runs fine.
I'll have to discontinue the rolling shut down into the garage. That sems to be what boogered it up.
I'll skip work tomorrow so I can ride about 8 hours. Just to be sure. It's the only prudent thing to do!

Thanks for all the help.
 
I had the same anomally with my 08Road glide.
Paradise HD thought it was a grounded out battery tender. It was pinched under seat. I don't think it was the issue because it happened afterthat afew times.
When it happens now i turn ignition on and off 4 times waiting 10 seconds
 
I am having the same problem with my '08 Ultra. The bike has less than 1K mile on it now, but the high idle started not long after I got it. I first noticed it on a trip across town on the interstate where I used the cruise control. When I came off the exit to a stop light the bike was idling at about 1300 RPM. After I reached my destination and shut the bike down it was OK again.

The second time was yesterday. I again was on the interstate with the cruise control on. When it came off the highway to the back roads it was idling at about 1200-1500 RPM. I made a stop, and when I restarted it was still idling high. It was about 45 minutes to home, when I arrived here it was still in the 1300 -1500 RPM range. I had added a S/E air cleaner and S/E slip-on mufflers reflashed the ECM the night before and I was thinking that I had accidently set the idle up. I checked my tune file and it was setup for 1000 RPM idle speed.

Reading the owners manual, and noting that this problem only appeared when the engine was hot and had been run hard, I saw the note about disabling the EITMS. I disabled the EITMS yesterday evening and my idle seemed to be back to normal. I ran the bike again today, under similar temperatures as yesterday, on the interstate with the cruise on and the bike idled fine after I came off the interstate.

I did one thing differently today, I did not disengage the cruise control by turning the throttle past "zero" as I had been doing, rather I used the brakes to disengage the cruise. My thinking was that I may have in-advertantly set the EITMS on with the throttle. I checked, with the engine running and the cruise on or off you can enable the EITMS by holding the throttle to the stop.

The curious thing is, according to the description the EITMS is supposed to slow the idle down to cool the engine not speed it up. Sounds like a software bug in the ECM to me. But what do I know, I've only been writing software for the past 20 odd years.

Ride Safe!
 
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You may be on to something there with the throttle roll off effecting the idle speed. Curious to see what the MOCO comes out with to solve this issue, probably another whopper like "rider error".
 
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