I know this topic has been discussed, but I have yet to see what values people have when setting the closed throttle position on their PCIII. The reason why I am posting this thread is that on Friday, I took the day off to spend the day riding. Well, it was around 32 degrees when I started up the bike. It idled fine at higher rpm's, but then as it started to warm up and go to a slower idle, it died, not once, not twice, but four times. I finally got on and pulled away and at the first light, same thing. Next light, same thing. The rest of my day went fine, but my stops were only for gas and lunch, and by that time, it was maybe 40 degrees or so.

So, yesterday, I hooked up the computer to the bike and PCIII. The closed throttle position was set at 3% instead of 0. So, I warmed up the bike for a few minutes, and when the idle slowed down, I reset the closed throttle position. Well, it continued to struggle idling and would spit and sputter, then die.

My questions are:
1. What rpm's should typical idle be?
2. What is a typical closed value position on the PCIII?
3. Is there another way to control how long the idle stays at a higher rpm?
4. What other things should I be looking for?

Attached are my recent values.

 

I have a 00EGC, last winter I fought the same issue for 6 months, finally had enough and took it to a dealer, they had the bike for a week just trying to set the warm and cold idle, they took my PCIII off and said I need a SERT. The bike ran fine once I picked it up but didn't have the jump it had before bringing it in, so I put the PCIII back on and 2 days later is was acting up again. Your issue could be totally different than mine, mine is the older MM fuel injection system I beleive was only used for 2 years. Good luck.

True duals
A/C kit
SS510G - cams
PCIII
Dyno

 

I'd say put some numbers in the idle area (1000rpm?) at zero TP in place of the 5s you have there. I'd also be inclined to put a few numbers in across the row as well. You could easily test it without your laptop. Just bump up the 'Low' RPM range fuel on your PCIII a couple of notches as a trial. I'd think that as you do it as the bike idles you'll hear it clear right up.
If it does the trick you could then write those numbers into your map. Remember that when you bump the numbers up using the buttons on the PCIII you increase all the cells throughout the RPM range the same amount. You maybe only want them in the 'zero' TP. This ought to solve the crappy running at idle. Messing with the zero throttle position isn't the way to fix this IMO.

1)I believe the idle is somewhere around 1000 rpm.
2)The closed position is supposed to be at 0. You're setting it so the PCIII knows the point at which you throttle 'sits' at zero.
3)IMO, the way to set idle properly is to add enough fuel at zero TP to make the bike idle nicely. (warm) I'd think the bike will take care of things when cold after the idle is set right warmed up.
4) I'd think your bike looks to run pretty lean at your settings. Just my opinion. I'd watch for signs of overheating. What are your timing numbers?




CN

 

So you reset your throttle position within the software, and you're having problems keeping it idling?
What's your 0% throttle position numbers at 500 rpm, 1000rpm, and 1500rpm? Unless they're pretty high, increase 'em by 5 or so. Do it at 2% as well. If it solves the problem, great..If it makes it worse, go in the opposite direction, and take 5 off your baseline numbers.
Sounds to me like you're running a tad lean however, so increasing fuel should solve it. Sure it's possible that you could be running too fat instead, but either way you'll know which when you make your changes.
BTW..don't worry if you don't have 500rpm cells, and don't worry if you do, but are concerned about changing it because your bike doesn't idle that low. It'll bleed into the next cell, and we wanna affect your idle mixture even if you drop under 1000rpm.
I personally like 1200rpm on street bikes, but you have no external idle adjustment capability on EFI HD's.

 

Thanks for the replies. I have updated the software and firmware and reloaded the map from Dynojet. I'm down and out today and am home watching my 2 year old who is also sick. When I get a chance, I will reinstall the PCIII and see what I have. I will reset the closed throttle position and then, if the engine is still stalling, will increase the low rpm fuel range on the PCIII and see what happens.

 

Edit - Oops, I see you have an 08 so none of this applies, however it could apply to the poster with the 00 so I will leave it.

Been watching the posts here, I have not had experiance with the PCIII so what I am stating here may not be of any usefulness. Could you be chasing your tail here? On the Magneti Marelli idle control, unlike the later Delphi style, the idle control physically moves the throttle plates and TPS values as it adjusts idle speed. If, for example due to an improper mixure, the idle control moves the plates further open as it trys to compensate for the proper idle RPM, the throttle position % would now be higher then when it was previously set to 0%. Let's say it is now 5% but if you reset it to 0%, then correct the mixture problem, the idle control will re-compenstate to a new throttle position value and the tune will be off again. Using this senario, maybe the throttle % should have been left at its 3%, then start tuning, it may have returned to its previously set 0% after proper low % fuel values programmed into the PCIII. Furthermore, possibly on an MM system, careful consideration would have to be given to the full range of the idle control on a PCIII for the full cold/hot throttle position % range of the idle control system.

 

I had a similar problem with my build and the PCV/AT. To get mine to start and idle when hot I had to go -27 fuel at 0 TP and 1000 and 1250 rpms. I then had to go to - 10 fuel for 3 seconds at start up. The moral of this story is to try different numbers untill it works.

 

The PCIII is likely not causing your idle problems, but to verify I would bypass it long enough to determine if the problem disappears. There were idle issues with '07's covered in TT410, and several have reported these here, including some with symptoms as you describe. I have this document in a PDF but I can't say if it would relate to your '08.

 

Well, I finally was able to test out the new settings on the PCIII today and managed a 75 mile ride. Temperature was around 50 degrees, so a little warmer than when the bike was acting up last week (32..brrrr).

On Tuesday, I was able to update the firmware and reload the map from Dynojet for my setup. I tweaked the map slightly based on Comfortably Numb's suggestions. I also reset the closed throttle position.

So, today was testing day as it has finally stopped raining. The biked started up nicely and I quickly noticed that moving from a stop was no longer a struggle like it was before when the bike was rather sluggish in first gear. The ride was great and the performance was just what I hoped for.

My ride took me 35 miles north along the Mississippi River on the Minnesota side, then back south along the river on the Wisconsin side. Fall colors aren't quite as good as past years, but that's ok, still great time to ride.

So, thanks to everyone who chimed in on my thread and special thanks to HDF for creating and managing such a great forum.