M&M injection high idle

[BONERACIN]

M&M injection on a Roadking, stays at high idle when started. Any suggestions on where top start. I have heard of the IAC valve causing this. Is there is a procedure for cleaning it? Any other suggestions? Any help would be great.

[PC_Hater]

Hot and cold idle are seperate systems.
Is idle only high when the bike is cold?
And check that it isn't just the cables that need adjusting!

[Ajayrk]

What year is the motorcycle?

[FLTRI]

You have a Magneti Marelli Idle Speed Control (idle speed controlled by adjusting screw) in lieu of a Delphi Idle Air Control (idle speed controlled by computer operated air valve).
This means your idle speed both cold and warm/hot are controlled by linkage/screw.
So, if your linkage has not changed my suggestion would be to look for an air leak. Most common is the intake manifold where it mounts to the heads. WD40 works to spray while idling right onto the flange and if the rpm changes you know. Just be carefull not to get overspray into the intake or it will produce a false reading.
HTH,
Bob

[BONERACIN]

It idles high hot and cold. I have checked for intake leaks and everything seems to be ok. It is a 99 year model. There has been no adjustments made anywhere. It had been setting up for a couple of weeks and when started it idled high, i ran it to get it hot and it still idled high.

[FLTRI]

A failing engine temp sensor will cause this condition especially if you notice it running rich.

[Papamte]

 1. Check your throttle cables and make sure they are not sticking. Also make sure you still have a bit of free play.
2. Check the IAC opening and clean it out with some good throttle cleaner.
3. Make sure the Idle speed controller is working properly. Remove the air cleaner and cycle the ignition and watch the controller. It should move in and out before settling down.
4. Check the miniature bearing in the side plate, and make sure it is not sticking or is rough when turning.
5. Reset the idle. After setting the idle warm, pull the fuse for 5 minutes to reset the ECM to the new idle setting.
6. If none of the above works or seems to last, then you may have a bad temp sensor.

[BONERACIN]

thanks for the help. I am going to check it out this weekend.

[tdkkart]

 My '01 Ultra had the M-M injection on it when I got it, one of the things I found was that when it started doing weird "Potty mouth" the first thing to do was to disconnect the battery for 1/2 an hour or so and then retry. Disconnecting the battery resets the computer and fixes alot of oddball issues.
If your bike indeed sat for a couple weeks and the battery was a touch low when you started it the computer may have had a glitch that is now causing the high idle.


Notice I said my bike HAD the M-M injection. I switched it over to carb about 3 years ago, best thing I ever did to it. The bike runs absolutely perfect now, no glitches, no wondering when it will leave me stranded.

[HD/Wrench]

Not to high jack the thread , But I just did a HPI t/b install for the MM system WOW!!!  new bike different animal. The bike is a 98 inch, with some mods. But like I said Dont want to high jack this guys thread. If you are working with the MMI systems these work extremely well.

[burnit]

My buddy just (yesterday) converted his 01 electraglide classic to carb - He has has had many many issues with the MM system over the years - I can tell you for a fact  - THE ISSUES ARE GONE - his bike runs better than it has ever run - idles perfect - no poping - he got stock carb, manifold and ignition from some guy that had upgraded - wiring harness from harley - Pingel adapter for gas tank - cost him about 350 dollars and a little time - less than a Dyno tune - If ya have the MM and are having problems / issues - switch to carb - used parts are available every where - cheap - and the problems are gone for good

Take Care
B

[Deye76]

Whenever there's a problem with an MM bike, also check the fuel line inside the tank for a hole worn through.

[HD/Wrench]

The carb conversion is another way to go. However for us in our area with huge elevation changes the carb is not going to work as well. keeping with a CV is the best way to go. Just had a conversation with a customer that a shop in Phoenix swapped his over to carb and installed a S&S G guess what he has issues. Poor milage, fouling plugs, runs great in phoenix though....

[BONERACIN]

This is a Texas bike not that many elevation changes. I have been tring to talk the guy into converting over to a Mikuni, but he is dead set on the fuel injection.

[HD/Wrench]

Then by all means use the HPI t/b you will not be dissapointed at all.