Idle Issue ?

[summitboy]

I have a 2012 S10 that i recently bought used. It now has 11,000km. The previous owner installed a full Arrow ex, PCV with Auto Tune, ECU reflash done by avc8130. Every once in a while the bikes idle starts to lope up and down between 800-1300rpm. Sometimes it will stall. I also noticed during a trip i was getting a lot of decal popping (lean condition). I solicited the help of a STF member who had me check a few things out with the PCV. I reset the Autotune time to 300 seconds, and accepted the trims. I then set the CO to +3 on both cyls. I need/want to do a throttle sync but am waiting for a Morgan Carbtune to show up.

After setting these few things i went for a ride. The decal popping is now gone as compared to before. The bikes fuelling seems to be spot on. No stumbles, misses and has excellent power throughout the entire range. I went into the city and shortly after i get this loping idle in traffic and the bike keeps stalling. It will start right away back into a lope and will try and stall again. I then drive around a little more and it disappears. Idle is rock solid. I visit with a friend and bike cools. I leave his place and shortly thereafter it starts loping and i get few stalls. I hit the highway for a little stretch pull the clutch in and it still lopes. Pull over to get some video and by the time i get my phone out it settles into a perfect idle. I then drive around town trying to get it to do it again with no luck.

I know i haven't synced the throttle bodies but what is going on ? LOL Ideas or thoughts ?

Thanks

 

[tubebender]

I am purely speculating here, so don't take this as gospel.

As I understand it, the Auto-Tune is a piggyback system that tries to fool the ECU (or manipulates the outputs, I'm not clear on that), where as the re-flash actually changes the look-up tables in the ECU.

If you had a re-flash, is it possible the Auto-Tune is messing shit up?
Have you asked AVC?

 

[summitboy]

That thought has crossed my mind. Not sure if the Autotune actually changes anything until u accept the trims. Its the weekend so i will tey and call/contact him. I havent done the sync yet either but i highly doubt its that. I went out to the garage and fired it up and i still get a very small lope 50-75rpm.

I did see another post about a guy who had Arrow pipes and had a similiar issue. Not sure if its that. Keep em coming

 

[summitboy]

In further reading it seems the AT is live. May be worth trying it not live or disabled. Interesting

 

[longride]

I have an idea. Put it back to stock and I bet it all clears up.

 

[cosmic]

I was planning to seek info on this matter too. Thanks to Summitboy i will just add that my bike is stock (Akra only) and the symptoms are just the same. I'm on 23k and I noticed this phenomenon since 3/4k mls. Even with the CJM on, it does the same thing, occasionally. Let say we can rule out the auto tune mods, at least in my case.
I'm thinking TB synchronization at 250 could solve this.

 

[summitboy]

I'd like to keep all the mods because it runs excellent other than a intermittent troublesome idle. I've ridden a stock one and it sucks lol. Way smoother, way more power, no restrictions. It hauls the mail. Has to be something fixable. Carb sync maybe ? I'm not gonna believe it until I see it ha ha. I have a Carbtune and a Harmonizer coming so ill rule that out soon. The only reason I'm somewhat hopeful to the TBS is because this is a idle issue only. It's 100% perfect above idle, no stumbles, no burbles, instant power. Has to be something in the idle circuit IMO.

 

[Don in Lodi]

As strange as it sounds, make sure of your coolant level. On several makes in the auto world if the coolant isn't covering the sensor 100% the idle will surge pretty dramatically. That and a vac nipple leak are the only things I can add.

 

[summitboy]

Coolant is nice and full. I did look at the hose and nipple that we use for the sync. They look good thus far. Il probably put a new cap and hose when I do the sync just to make sure. The bike was more or less like new and clean. The rubber still feels supple etc.

 

[Karson]

Post up your PCV map

 

[summitboy]

Well i went on another ride over 3 days (1500km) i never saw this idle issue. Sync is still to go. I do still have some decal popping in that 3-4000 range. No surging anywhere etc ! Kinda strange imo. I'll see what the sync says on Monday. Got the Harmonizer in the mail today. This S10 runs very strong !