Some of you know that I recently picked up "Elvis" (2007 FLHTCUI) after selling my 2000 Fatboy.

This is the first bike I have ever owned with Fuel Injection. I'm just starting to get a chance to ride the bike some (weather) and I now notice that the Idle surges a back and forth a few RPM (between 950 RMP - 1050 RPM) which my carb bikes never did...and if it did it was usually related to the idle mixture or air leak.

I'm sure this has been discussed, but a search of the forum only talks about surges under 2000 RPM...does that also include the idle?

What's the cause and what's the fix? I'm looking at picking up an XIED from Nightrider prior to summer. Would this fix it by richening up the mixture or is this issue related to something else?

Thanks!

 

A couple of times I have noticed that my 07 will just about lose it's idle at a stop. If I turn the bike off, then restart,(waiting for the dash light to go out before cranking), it resets the idle rpm and all is good. Since I installed the PCIII, it's only done it once. might give that a try.

 

Before the PCI III did the RPMs flucuate while idling (like start up or even after a ride)?

It's liveable, but figured maybe it is some known issue with the 2007. I have to take the bike down to the HD dealer for a safety check, I'll probably ask them...gee...I hate to have to...I always do my own work and troubleshooting and fixing...just a Fuel Injected bike is something I don't know much about and whether this is normal (RPM flucuating).

Thanks!

 

Not normal

 

SSN711, when you start the bike, are you allowing the Fuel Injection system to fully 'prepare' (there is a red key icon on the tach [Ultra] that you're supposed to let extinguish before you start the bike.

There were a few times that I was in a hurry and forgot to let that process fully complete and when I started the bike (my '07 Ultra), the bike idle was a bit off of its normal...

Hopefully your dealer will help you out @ no-charge.

 

Uhhhhhhhhhhhhh....gee, no...never checked....oops! Thanks! Will check tonight! Hope it is something that stupid...uh, simple....

 

That's the light I was refering too also.

With the PCIII, if you don't wait for the light, the bike will start instantly. If you wait, it will turn over once or twice before the motor catches. I will say that since I have gotten into the habit of waiting for the light to go out, I haven't noticed any idle issues.

I can't remember any idle issues when the bike was stock. I did the PCIII in probably the first 1000 miles of buying it.

 

This light thang and with the PCIII

The PCIII will reboot itself after a few seconds(6-10) of turning the key, so it you fail to time it correctly, you will experience slow starts and lumpy idle due to reboot.

If running stock ECU, then wait till red key light goes out..... if running PCIII piggy back to stock ECU, then listen for fuel pump to pressurize, then start within 2-3 seconds of turning key.

If running stock and after waiting till red light goes out and you still have a problem, then approach dealer and demand he reflash ECU for free.

 

HA HA HA URRR FUNEE! That and two bucks might get you a cup of coffee. I have found it much better to approach the Steal...er Dealers with the I seem to have a problem can you help attitude. Much more likely to get some free help that way....Just my .02

 

My '07 SG doesn't vary much but idles rougher than my old Evo or any TC88 I've ever ridden, and this is a characteristic of the pre-'09 TC96's. My EFI setup is totally non-stock with a PCV with Auto-Tune, which changes the complexion of everything.

IIRC the '07 stock EFI setup runs in closed-loop at idle, which I suspect is the cause of your "searching," but adding the Nightrider gizmo may or may not make a difference there. It might help simply because it enrichens the AFR slightly, even though the O2 sensors might still make the bike "search" like it's doing now. The downside is that it isn't adjustable, so it'll either help or not. I would find someone with the XIED who can give you first-hand info.

This device simply tricks the computer into thinking the AFR is higher than it really is and causes it to run at around 13.8:1, 14.2:1, or whatever it is nowadays, but only in the limited closed-loop range provided by the narrow-band O2 sensors. This device will cool the bike in the cruise range but will not affect those areas above about 3k RPM and 40% TP (throttle position), which means it will not improve performance over stock in the open-loop areas. This to me is a huge disadvantage over most other EFI controllers.

Even though a more expensive proposition, I would instead go to something like the PCV, which will allow AFR alterations everywhere in the RPM/TP range, including idle. Used alone, i.e. without Auto-Tune, it runs in open-loop mode, so perhaps this will help with the "searching." With AT it is set to run in open-loop at idle anyway, so that shouldn't change things. The good news is that it is very adjustable and you can play around with idle mixtures for one that feels the best to you.