I have a 2001 FLHRP with stock motor, and pipes. The only after market thing this has is an Arlen Ness Big Sucker stage I air cleaner. The idle has been dropping between 400-600rpm at idle. and when the idle drops to this level, the check engine light goes on...I give it some gas to get it up to 900 and the light goes off.

I pulled the plugs and they was some carbon build up, so I cleaned it off and that raised it a little.

I tried the revtech dfo, but it didn't do anything.


I am used to carbs so this EFI is new to me...is there a quick fix to raise the idle speed up without having to remap or buy a race tuner or power commander (which is my next option).

any suggesstions would be great.

thanks,
Larry

 

As far as I know, there is no way to increase the idle speed with EFI, without remapping it.

 

thanks,

so it will have to be race tuner or power commander correct? or put the stock air cleaner back on

Larry

 

On the early touring models that had the Magnetti-Marelli EFI you could adjust the idle. just do a search and there are some articles about it. Usually if your idle drops when you stop, try looking at the IAC (idle air control) valve, sometimes you can remove the valve and clean the seat with carb cleaner spray, or look to see if you have a leak in the intake manifold gaskets, the IAC will interperate a fluctuation of the vacuum signal and try to compensate for it.

Try this, https://www.hdforums.com/forum/touri...dle-speed.html

 

Your problem is the ISC or the Idle Speed Control Actuator. It needs to be replaced, also check the cam assembly for the actuator. They will wear and tend to stick. Once you replace it, here is how you adjust the idle speeds. Unplug the ISC you just installed and start the bike, adjust the cold idle to 1500 rpm's. Then plug it back in, and start the bike.
Let it warm up and adjust the warm idle to between 950 - 1000 rpm's. Then shut the bike off, disconnect the battery and let it sit for 10 minutes. This allows the ECM to clear it's memory and learn the new idle speeds. That should do it for you. You will see a plunger built into the ISC, it operates a lever which inturn turns the cam for the throttle. Be sure it isn't sticking and rotates back and forth freely.. There is also a voltage adjustment for the ISC, but that requires the use of a Scanalizer. You should be fine just replacing it and following the idle setting procedures I described above.

Stroker

 

By the way, the idle speed adjuster for your M & M system is behind the air filter plate. You will need to remove the air filter and back plate to see it.. It's a small torques screw on the bottom right hand side. It's at the bottom of the cam I was talking about.

Stroker

 

I had the same problem on my 01' Ultra. The actuator plate was sticking and would upset the idle speed control. I tried adjusting the cold idle speed several times, but it would mess up after a week or so. I removed the idle actuator plate and found the miniature bearing was rough to turn. Called Motion Industries and picked up a new miniature bearing and installed it. My idle idle problems were solved. Most likely that is your problem too. I doubt if the idle actuator is bad.

But it could be! The mini bearing is a cheaper fix too!

 

thanks for the tech info stroker

I replaced the idle speed control unit about a 1000 miles ago...the idle just started dropping a couple of hundred ago...

I turned that torx screw and everything idles between 900-1000 now....

thanks a bunch...

I had a revtech dfo, plugged in before but thought that would solve the problem but unhooked it....do you think the dfo makes a difference on this efi system or should I just go race tuner or PC?

thanks

 

papamte

where is that bearing located? is it that plastic thing on the left side of the throttle openings that is held with 2 sealed torx screws that is stamped M and M?

Larry

 

lc1484, the plate is on the right side of the throttle body at the end of the throttle shaft. It is moved by the idle actuator. Just remove the lock and nut, and work the plate off of the actuator. The mini bearing is pressed into the center of this plate. It's easy to replace, and the price of the bearing is minimal. I set the cold and hot idle again and no more problems with my idle.
Get the number off the bearing and call your local bearing supply store. A generic replacement is just fine and costs only about $4.00. This is a sealed/shielded bearing.
If the bearing is bad the actuator senses this and tries to adjust, and then just backs off. This why the idle will just drop out. Mine would drop to about 600 rpm and the bike would usually die if I didn't roll the throttle a bit.
I'm not saying that the actuator couldn't be bad, but just offering my own experience which sounds virtually the same.