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Hi,

I have an '01 fuel infected Roadking. Last year I noticed that it rarely went into high speed idle when cold. By the end of the season it was idling low, around 700, 750 rpm. According to the manual I am supposed to hook up a diagnostic tool to a connector, find a voltage and make adjustments.

The connector has 4 pins according to the wiring diagram. Does anyone know which 2 of the pins will give me the voltage reading?

Or, does anyone have any ideas to correcting this issue?

Thanks,
 

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When mine acts the same I clean and re-oil the air cleaner and replace the plugs and idle speed returns to normal.
 

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Here's an easier way: get your bike to operating temperature (this part is important). Disconnect the ISC plug (the one on top of the throttle body). Adjust the cold idle to about 1500 rpm's. Turn the bike off; put it back together; and pull the ecm and fuel pump fuses for a few minutes (under the right side cover). You're done. (after you replace the fuses)

Ragnar
 

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I had the same problem with my '01 (MM efi) Road King Classic. I was able to increase my hot idle up to spec (950-1050rpm) by simply turning the idle adjustment screw clockwise. I didn't use a SCANALYZER, and I didn't disconnect any fuses.

Here's how:

Go for a ride, make sure bike is up to temperature. Remove air cleaner. Insert a T10 TORX head through the appropriate hole in the backing plate (see image). The actual adjustment screw is behind the plate, but it's easy to engage the TORX. Turn it clockwise to increase idle. Button her back up and you're good to go.

I think the problem is that the adjustment screw actually slowly backs itself out. Mine's been good for several months, but if I need to adjust it again, I'll probably add a drop or two of blue loctite.

 

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I agree, Sinker. I think on some bikes the idle adjustment screws have a tendency to back themselves out over time. It wasn't clear from the question if the warm idle was okay or not, but if it's too low, the cold idle will be too low as well. May as well do them both. I would also pass on the voltmeter and Scanalyzer.

Ragnar
 

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Ragnar said:
I agree, Sinker. I think on some bikes the idle adjustment screws have a tendency to back themselves out over time. It wasn't clear from the question if the warm idle was okay or not, but if it's too low, the cold idle will be too low as well. May as well do them both. I would also pass on the voltmeter and Scanalyzer.

Ragnar

For some reason I tought he was asking about warm idle....just re-read it and maybe not.
 

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Discussion Starter · #7 ·
Ragnar said:
I agree, Sinker. I think on some bikes the idle adjustment screws have a tendency to back themselves out over time. It wasn't clear from the question if the warm idle was okay or not, but if it's too low, the cold idle will be too low as well. May as well do them both. I would also pass on the voltmeter and Scanalyzer.

Ragnar
The cold idle hasn't really worked since last summer. The warm idle dropped last fall. As a matter of fact the bike used to get to fast idle and drop pretty quickly, and it's been some time since it has done that.

Thanks for the help everyone. I will do both the cold and the hot. I am confused though as to why I would get the engine to operating temp to adjust the cold idle?
 

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You probably don't but if you have the SE race tuner for the MM fuel injection you can plug the bike into your computer and check your throttle position sensor voltage and your idle rpms.
 

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Could be the idle air control (IAC) is stuck. The IAC is a motorized device that jack-screws the idle setting up at startup and slowly reduces it back to normal during warm up.
 

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Thanks for the help everyone. I will do both the cold and the hot. I am confused though as to why I would get the engine to operating temp to adjust the cold idle?[/QUOTE]

The easy answer is because that's the way the manual says to do it. "Cold" is a range; by getting the engine to operating temperature and disconnecting the ISC, you remove the variables. There is a way to set the cold idle with a cold engine, but the engine has to be ice cold, as in first thing in the morning. Start the bike and adjust the cold idle so it is between 1200 and 1300 rpms. You must do this fairly quickly because as soon as the engine begins to warm, it won't work accurately. This is an old garage mechanic's method, and gives kind of a ball park result, but it can work.

Ragnar
 

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`05 FXDI
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Sinker said:
I had the same problem with my '01 (MM efi) Road King Classic. I was able to increase my hot idle up to spec (950-1050rpm) by simply turning the idle adjustment screw clockwise. I didn't use a SCANALYZER, and I didn't disconnect any fuses.

Here's how:

Go for a ride, make sure bike is up to temperature. Remove air cleaner. Insert a T10 TORX head through the appropriate hole in the backing plate (see image). The actual adjustment screw is behind the plate, but it's easy to engage the TORX. Turn it clockwise to increase idle. Button her back up and you're good to go.

I think the problem is that the adjustment screw actually slowly backs itself out. Mine's been good for several months, but if I need to adjust it again, I'll probably add a drop or two of blue loctite.

Sorry to butt in but your post actually answered my questions. I have an 05 FXDi and I've always thought my idle was way to high at warm idle. In fact it sounds like it's still at cold idle and I can't "hear" any difference between cold and warm. It has done this since I first got the thing. I don't have a tachometer and I realize I really need one to do this right but I think I can adjust it by ear until I can figure out a tach setup. There has only been one time that my bike had a low idle and I thought it was overheating because I read that if it gets to hot the timing is retarded by the computer or it only fires on every other revolution.
 

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Not a good idea to adjust the idle speed with the screw!!
It should be done thru the ECM(aka SERT):whistle:
 

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Kriz......Your bike has the Delphi efi.....these guys have been discussing adjusting idles on the Magneti (MM) efi. These methods won't work on your idle......the Delphi has to be set by the dealer or SERT.

'05 should still be under warranty? Let the dealer take care of it.
 

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`05 FXDI
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Ahhhh!! Thank you for the correction. I didn't know there was a difference. Well $*&@#, I had hoped I could fix it. I don't think the dealer will fix it. I've changed the pipes and done my own oil changes. According to them I voided my warranty. :whatever: :2flips: I also don't want to upgrade to the SERT. HD wants way to much for that package. Anyway I'll exit this thread now since it doesn't concern my EFI. Thanks for the info though. Learning more every day.
 
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