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DesertHog
25th February 2010, 07:05
Hi all; I've encountered a throttle problem with my '08 XL1200C. After riding for 45mins or so, or until the engine is hot, the engine won't return to idle on closing the throttle. The throttle grip itself snaps closed OK but the motor continues to run at high revs. Once I get stopped, say at traffic signals, after 30-45 seconds the idle speed will reduce to normal. Also if I hit the kill switch and then immediately re-start, the engine will re-start at normal idle revs.
I've tried adjusting the throttle cable adjusters, which seems to help a little, but because the problem can't be replicated at a standstill it's proving a real PITA to sort. Dealership can't find a fault code anywhere either.
Any advice or suggestions would be most welcome.

FoxsterUK
25th February 2010, 07:28
I understand this to be fairly common on some EFI Sportsters. Do a search using the Google search at the bottom of the page and you should find other posts on this.

jharback
25th February 2010, 07:47
I understand this to be fairly common on some EFI Sportsters. Do a search using the Google search at the bottom of the page and you should find other posts on this.

Have you tried using the Google search function lately. You get everything but, what your looking for. Boolean operators don't work so you end up getting everything. Might as well page thru the appropriate forum.

DesertHog
25th February 2010, 09:15
I understand this to be fairly common on some EFI Sportsters. Do a search using the Google search at the bottom of the page and you should find other posts on this.
I did search this and other forums before posting and found a number of threads relating to throttle and cable adjustments on carbed models, but nothing related to these symptoms. Will keep looking. Thanks for the reply.

Bob F
25th February 2010, 11:53
Video the problem to document it. The dealer should be able to duplicate the problem with a test ride. If all else fails, Harley Davidson Customer Service 414-343-4056.

Baphomet
25th February 2010, 14:16
Hi all; I've encountered a throttle problem with my '08 XL1200C. After riding for 45mins or so, or until the engine is hot, the engine won't return to idle on closing the throttle. The throttle grip itself snaps closed OK but the motor continues to run at high revs. Once I get stopped, say at traffic signals, after 30-45 seconds the idle speed will reduce to normal. Also if I hit the kill switch and then immediately re-start, the engine will re-start at normal idle revs.
I've tried adjusting the throttle cable adjusters, which seems to help a little, but because the problem can't be replicated at a standstill it's proving a real PITA to sort. Dealership can't find a fault code anywhere either.
Any advice or suggestions would be most welcome.

On another forum I frequent a guy has an 08 Ultra that did the high idle thing and said he did a reset with the ignition (cycle on off 4 times then start) and the idle was no problem after that.

I am not suggesting that this will solve your issue, but it does point to a glitch in the ECM software which there might be a fix for by now. Perhaps your dealership doesn't keep on top of tech bulletins, or maybe there isn't a tech bulletin. In either case, since the problem doesn't seem to be mechanical I would go on the assumption that it is ECM related.

Bone
25th February 2010, 14:21
I understand this to be fairly common on some EFI Sportsters. Do a search using the Google search at the bottom of the page and you should find other posts on this.

Not really, MOST idle complaints on EFI bikes (stumbling or running a bit high) has to do with cold startup.

This might be the first I've heard that is definitely when the motor is fully warmed.

My guess?

IF shutting it down and restarting didn't fix it I would say it COULD possibly be mechanical (say a vacuum leak that becomes more pronounced when it heats up to a certain point).

BUT because shutting it down and restarting makes it go away it's electrical.

Either a problem with the idle speed control logic OR possibly with the idle speed control valve itself.

DesertHog
25th February 2010, 16:41
Not really, MOST idle complaints on EFI bikes (stumbling or running a bit high) has to do with cold startup.

This might be the first I've heard that is definitely when the motor is fully warmed.

My guess?

IF shutting it down and restarting didn't fix it I would say it COULD possibly be mechanical (say a vacuum leak that becomes more pronounced when it heats up to a certain point).

BUT because shutting it down and restarting makes it go away it's electrical.

Either a problem with the idle speed control logic OR possibly with the idle speed control valve itself.
Bone - I had the same thoughts regarding it being electrical in nature, thanks for confirming. It's due a service shortly so I think it will be in to the dealership and ask them to look at it again and take it for a TR if neccessary so they can witness the fault first hand.
Thanks everyone for your thoughts and suggestions.

byidesign
25th February 2010, 16:58
Go to the Forums for EFI/engine codes...and download the {how to} for engine diagnostics...then pull the codes from the scoots ECM .It sounds like you will find the "P0505"{loss of idle control} or IAC {idle air control,actuator} error code in the code storage..it is a warranty replacement ..just read the codes {don't reset} that way you can prove it has a problem to your dealer..
{see "how diag codes work" }posted in this forum
hope it helps
Bruce

Bone
25th February 2010, 17:03
Go to the Forums for EFI/engine codes...and download the {how to} for engine diagnostics...then pull the codes from the scoots ECM .It sounds like you will find the "P0505"{loss of idle control} or IAC {idle air control,actuator} error code in the code storage..it is a warranty replacement ..just read the codes {don't reset} that way you can prove it has a problem to your dealer..
{see "how diag codes work" }posted in this forum
hope it helps
Bruce

I agree it's a good idea to check codes himself.

But FYI, in the original post he said the dealer checked and found none.

Not that I trust the dealer necessarily.

IF the OP does check and finds a code, take a pic with a digital camera in case they deny it again...

DesertHog
25th February 2010, 19:44
Good advice - I will try to check the codes myself. Thanks again to all.

linkin5
25th February 2010, 20:01
My 07 1200R does this also, it has since new and throws no codes and the cables are in adjustment. It probaply is a software issue but is a small problem compared to all the other issues of the new bike, When I installed the PC III for the stage one changes it improved alot and isn't real noticable anymore. The PC III also improved my cold engine stumble and my good gas mileage issue.

Screw Loose Dan
25th February 2010, 20:17
When you say high idle, do you have a tach? Is it always consistent RPM's? Do you have a any fuel management system? What mods (air cleaner, exhaust, etc)?

I know you said that the throttle "snaps" shut, but pull the air cleaner (presuming you have a stock air cleaner) and visually verify that the throttle plate actually fully seated against the stop (the FSM has a decent diagram, but it's pretty obvious when you look at it). Visually make sure it actually snaps shut with the handlebar in ALL positions. Yeah, might be redundant, but it's a cheap fix.

Also, pull the connector for the IAC and make sure there is no corrosion anywhere. You may also want to use a "sensor safe" carb/throttle body cleaner on the sensor.

I would also make sure the engine temp and IAT connectors are secure and clean. The only things I know of that will induce high idle "electronically" are the starting the motor and cold engine temps. If there's a loose electrical connection causing the ECM to think the engine is running cold might cause an issue like this.

qaz1
25th February 2010, 23:59
I had the same bike as you that had the same problem along with the cold start stumble. The cold start stumble was never fixed and was the reason I traded it in for a Dyna last year during the trade in your Sportster for msrp Promo. They were able to fix the high idle problem using the method that Baphomet said. The tech said if you turn the ignition switch on and even slightly turn the throttle, after several times of doing this the ECM uses that point for "zero". They reset my "zero" point and all was well..............Except for the dreaded COLD START STUMBLE, which I eventually fixed by trading it for a Dyna. There is a long thread on the STUMBLE and the new fix they have so if you also have that issue bring it up to the dealer.
Good Luck

byidesign
26th February 2010, 21:51
one thing I also found with mine{after @ 6Kmi]..a little erratic...but showed no codes{07-883}it was that my rear exhaust pipe to engine head bolts had loosened up,and I had to re torque them... a mechanic friend of mine ...said it can mess up the O/2 sensor readings, and cause misreadings to the ECM.{variable idle speed}
check for intake /exhaust fastners loosening up...it could be that simple a fix....

brya0143
12th March 2010, 20:26
I have the EXACT same problem. I've brought it in to the dealership like 4 times. They ride it and say they can't repeat the problem. You feel like a complete idiot cruising up to a stoplight with your idle doing triple-time. They tried to tell me that sporty's are super sensitive to cold weather and that because I was riding it for "so long", the engine cooled off.

Seriously? It's done it at warm temps too (like 70-80). I get the feeling it's significant and they will magically discover the problem once my warranty runs out here in a couple months.

I had no issues until they installed pipes and downloaded an ECM update for it. I was planning on brining an mp3 recorder with me next time I ride, and then leave at the dealership until they figure it out...

It drives me nuts and I hope one of us gets it figured out soon. I've had the air cleaner and throttle cables checked...blah blah. I used a PCV for a while, bypassing the O2 sensors and it still did it then too.

DesertHog
13th March 2010, 19:02
Glad it's not just me - I thought I was going nuts :banana. It's been OK for a week or two but for sure it's NOT related to the cold - I'm in the Middle East and we don't do cold!! I plan on getting a stage 1 finished soon and maybe as per another post that will sort it out.

DesertHog
13th March 2010, 19:12
Screw Loose Dan
Thanks for all those suggestions. I did get S/E pipes fitted but the problem didn't start then, actually started now I think of it when the battery was changed (the heat here in the summer eats batteries). No other mods and the degree of 'overspeed' varies and gets worse the hotter the engine gets. I'll check the throttle plate closure as you suggest too. Thanks for the tips.

BTW re your sign off, I have the pleasure and honour (Brit spelling - sorry!) to ride every week with a number of guys (and gals) who serve in the US forces out here in the Middle East - I couldn't ask for better riding company.

colebane
14th March 2010, 05:06
i have an 04 with the same problem. i have switched out ignitions from twin tec to crane. i switched carbs to mikuni and all the cables, routings and adjustments. and still it does it. i never heard of the cycling the ignition. i will try that. hope its that simple

Dormouse
12th September 2011, 12:51
I have had this exact fault on my bike since June 2010 and the dealer has been unable to find a cause, no fault found, it has been in and out of three dealers workshops on a regular basis (I moved house) over the pas 18 months. They have changed manifold seals, relay, idle control stepper motor as well as fitting a stage 1 (at my cost). Fault is still there. The warranty has now expired , the technician did finally manage to experience it, and they are now suggesting I have to pay for further investigation, and that it may be the Kitech fueller (which was fitted to try and cure the fault!).
So - has anyonewho has had this problem actually cured it?

leo310
14th September 2011, 01:26
http://xlforum.net/vbportal/forums/showthread.php?t=1091097

slideman
8th October 2011, 21:31
My 09 1200 does exactly the same thing, and I get an error code (P0505) that says Loss Of Idle control. Clymer manual says to look for a vacuum leak, to start with. Where should I be looking?
Thanx

slugga_308
31st October 2011, 11:03
Hi,
Another sporty here with the exact same issue. 2008 1200c. Has there been any update on a fix for this? Got mine booked in at the dealers next week. Will post an update after I get the bike back.

leo310
1st November 2011, 17:16
Here's an update. After having mine fixed with a replaced idle air control (IAC) valve less than 10,000 miles ago. It has started again. Same thing, maybe with more vigor this time. In my experience, having owned two, Harley Davidson motorcycles have lived up to their reputation. We all know what that is, I'm just saying.

Iron-knee
1st November 2011, 17:46
I had the same thing happen one time on my bike. It was at the end of a long trip on a hot August day. The RPM's were around 2500 with the clutch in. I came home, parked it, and it hasn't happened since. Subcribing so I know what to do if it comes back.

48er
1st November 2011, 21:09
I had the same prob for month and it was almost driving me crazy, because you are not able to reproduce the fault..
After checking the exhaust bolts ( two have been loose - but careful !:they only get about 12nm) and pulling back the two sleeves of the gas cables for about 2 cm towards the efi ( which gives them more space to the edge of the hot cylinderhead ) the idle problem has gone.
These two hinds I found in the net helped me..
Hope you all get rid of this prob, too, because I know how it steps on one's nerves!
Dirk

Please excuse my bad English - I'm from Germany..

RIDERED67
2nd November 2011, 00:27
Sorry I'm late to this but I have the answer to all your problems! (whether or not you choose to believe me is up to you.....dun dun dun) Its easier than you think!

I ride an electraglide all day everyday for work and I have been doing it for years. I am on my third Fuel Injected electraglide(currently a 2008 model) and I have dealt with this high rev issue on each one of these bikes. (on a side note I personally own 3 fuel injected harleys and never experienced this on a personal bike)

So here it is......All Harleys have two on/off switches (the run switch on the handlebars and the ignition switch that your key goes in)

The normal Harley starting sequence is;
1. Turn key ignition on
2.turn handle bar switch to run
2.wait for engine light to go out
3.Depress start button

To turn bike off;
1.turn run switch off
2.turn ignition switch off

The problem with these methods......

The ECM calibrates your throttle grip idle position each time the handlebar switch is turned on and off with the expectation that you are not putting any pressure on the throttle grip with your hand at that time. Chances are your hand will be on the throttle during this procedure and possibly not allowing the throttle to remain at its natural position of rest.

So if your putting pressure on the throttle when you hit the switch and the ecm incorrectly calibrates the throttles idle position you will have a high idle

The fix.....

I can never remember if the handle bar switch needs to be on run or off during this step so try both ways. (i am fairly certain it needs to be on). So turn the handlebar switch to run and the turn your ignition switch from off to run 4 times ending on off. This will reset it. Once you reset it your idle should be back to normal

To prevent it from happening in the future....

LEAVE YOUR HANDLEBAR SWITCH ON RUN AT ALL TIMES AND TURN THE BIKE ON AND OFF WITH THE IGNITION(key) SWITCH!

Ive been doing this for years with no adverse affects and it solves the high idle problem.

Sorry if this was to long.....

Baphomet
2nd November 2011, 01:12
The fix.....

I can never remember if the handle bar switch needs to be on run or off during this step so try both ways. (i am fairly certain it needs to be on). So turn the handlebar switch to run and the turn your ignition switch from off to run 4 times ending on off. This will reset it. Once you reset it your idle should be back to normal

This sort of confirms what I posted a year and a half ago which everyone chose to ignore. You had the details I did not, however. Maybe someone will actually try it now. I know it worked on my 08 when I tried it.

leo310
2nd November 2011, 08:25
Ridered67, No your answer was not too long, thanks for the input. I always cycle the power with the key not the on/off switch.

In my case that I've been documenting for two years, the bike idles fine, until.... 10 miles or so of non-stop cruising. Then it creeps up to 1,700 rpm, 1,900 rpm, 2,000 rpm, 2,200 rpm, and even 3,500 rpm.

In Los Angeles, lane splitting is legal, so I go 20 miles easily under this condition, twice a day, everyday, over 27,000 miles on my 08 fuel injected roadster 1200. Once a complete stop, and wait (with no wheel motion), idle then readjusts to normal 1,100 rpm.

Then the cycle repeats. Bike Idles fine, then creeps up, take to dealer, several times, delear replace IAC, cycle repeats, bike idles fine. 10k miles later problem re-appears... etc... totally friggin ridiculous...

leo310
2nd November 2011, 08:29
I will try your off to run 4 times suggestion in the morning (both ways, switch on and off) and post the result, thanks for the suggestion.

andyb
2nd November 2011, 14:21
regarding the "using the ign key to start & stop engine" is fine for the touring bikes, as the throttle bodys are electronic - otherwise known as "fly by wire". that means there is no mechanical connection between the hand grip & the throttle body - it's simply an electronic signal sent. but, in the case of the Sportster, there are still throttle cables connecting the grip to the throttle body, so there is no resetting the idle by turning the key on & off.

RIDERED67
2nd November 2011, 16:29
regarding the "using the ign key to start & stop engine" is fine for the touring bikes, as the throttle bodys are electronic - otherwise known as "fly by wire". that means there is no mechanical connection between the hand grip & the throttle body - it's simply an electronic signal sent. but, in the case of the Sportster, there are still throttle cables connecting the grip to the throttle body, so there is no resetting the idle by turning the key on & off.

Yea.... I understand what your saying here. Good call.

TP_Wade
3rd November 2011, 06:41
I've had the same exact problem on my 08 nightster. I'm running a custom set of pipes and intake. also running the PCIII "Powder Commander 3" I've made it better by messing with the throttle position in the tuning software. I've almost elminated it now and it only does it once in a blue moon. It has to be the throttle postion sensor or something of the sort.

leo310
3rd November 2011, 08:24
You may be right about the throttle position sensor. I did try cycling the key, like 8 times both ways for good measure heading out, another 4 times coming back from work.

On the way to work, at my exit the bike idle continuously crept reaching 3,700 rpm all through the fwy exit while stopping. Still sounding as if it wanting to haul ass while stopped. Just like the video I posted on youtube. On the way home, 3,500 to 3,700 or 3,800 rpms, clutch pulled in, no throttle around 10 mph splitting lanes for miles. For reference, these 1200s will do ~80 mph at 4,000 in 5th gear.

This goes way beyond idle, it is uncontrolled engine reving. It could cause a serious accident. I believe this will be way more prevalent as time goes by as more people rack up miles and experience with these sportsters.

I unhooked the battery and the ECI unit and re-connected. Will let you know if that'll make a difference. I sure hope it does, a long shot but next stop is another letter to Harley-Davidson, a call to the customer service center and a trip back to the dealer. It will be at least the 4th time.

slugga_308
7th November 2011, 10:55
Update on my bike.

Took my bike to dealer. Issue happened on the way in there.

Dealer checked and cleared fault code (p0505) and test rode and said they couldn't replicate the fault. (every time I pull up out the front of the dealers the bike is either working or the idle returns to normal)

Problem happened 3 times on the ride home. (took a detour for an hour).
Problem happened about 10 times the next day on a 3 hour ride.

I'm leaning towards and ECU problem or an IAC motor problem.

Lots of questions but just thinking out loud here.....

Does anyone know what inputs the ECU looks at to determine how its going to control the IAC motor? and what is the maximum engine revs the IAC valve would be able to obtain with the throttle butterfly closed fully? I'm guessing it would be around 2500 - 3000rpm? as thats the maximum idle my bike gets stuck at. The revs always return to a normal idle but only once the bike is stationary (or restarted while riding) so there has to be some input from a speed sensor. Also should the IAC valve normaly be shut while the bike is in motion and only open when the throttle butterfly is closed or is it at a pre-determined opening all the time and just fine tunes its positon when idling?

Thanks guys.

Will keep you posted of any success or failures I have trying to resolve this.

Hows everyone else with this issue going?

leo310
9th November 2011, 15:52
My bike is in the shop right now getting this issue fixed again. Idle almost always returns to normal when stopped (1 time it didn't, had to turn it off). That's the nature of the problem, engine over revs only when moving, at the slowest of speeds, down to slower than a crawl.