Bryan Zurlo

Back in April I completed a H/C/I swap on my 02 Z06, got it tuned and have been very happy with the car. Only thing that I don't care for is the fact that 9 times out of 10 when I am coasting to a stop with the clutch pushed in, the engine will maintain 1200-1500 RPM but the second I come to a complete stop, the engine will drop to the correct idle speed.

I've done some digging around on the subject and read about a few guys disabling the throttle cracker and follower. Figured it couldn't hurt so I did that and love how the engine comes back to idle more quickly and directly back to the correct idle speed without any sign of the idle speed hanging whatsoever. However, sometimes the engine will also drop way past idle speed and sometimes die. Any way to prevent this? The tune is attached for you to look at.

Attached is the current tune and the specs of the H/C/I swap are below:
Tick Performance SNS Stage 3 235/243 .630/.610 111+2
TEA Stage 2 head work on 243's
FAST 92
LS2 TB
1-3/4" LG Super Pro's

Any feed back would be appreciated!

Bryan Zurlo

Couldn't tell you, that's the tune my tuner did.

G Atsma

I deleted the question. Wasn't sure it was a valid one.

LilJayV10

iTrader: (39)

you need to post a log. make sure you log STIT/LTIT, desired air flow, actual airflow, follower and cracker.

Bryan Zurlo

Meant to attach one in my original post, sorry about that! Attached is a scan I just took and the hanging idle didn't seem to be as bad today, I've seen it hang around 1500-1600 RPM. At 14:43:00, 14:44:51 and 14:46:00 you can see where the idle is hanging and then drops to the correct idle speed when speed is 0. It looks like timing drops to almost nothing each time idle returns to normal.

As far as the scan goes, for one reason or another I couldn't get desired and actual airflow to populate on the chart vs time section but it did show up correctly on the channels section.

Any feedback would be appreciated, thank you.

Kfxguy

iTrader: (1)

For the sake of me not having to type all of this over, look at what I posted. It applies to this too.

https://ls1tech.com/forums/pcm-diagn...all-dying.html

Bryan Zurlo

Thanks for the feed back, and I understand where you mention that IAC and idle config need to work together. Question for you though, since C5's don't have an IAC what other tables would you recommend I look at? Idle cracker and follower?

Kfxguy

iTrader: (1)

Well in that case since you have a motorized throttle body, I'm not sure. I haven't tuned one of those yet. I've only done cable operated so far. You may have something called a rolling idle in the under the idle speed tab. See what this is, if it's 1200 then lower it and put your cracker and follower settings back. If you don't have that option, then maybe back off the follower just a little at a time to see how it does.

patSS/00

iTrader: (6)

Check whether it only happens with the A/C on. Also check whether DFCO is enabled.

Darth_V8r

iTrader: (4)

Electronic throttle uses a torque follower. Systematically reduce to torque follower table.

Bryan Zurlo

Thanks for the feedback, will give that a shot when I get back home.