Just made a boatload of changes new Rebel Intake, LS4 is back in and alky is currently off. Idle wasnt that bad prior to the change. Idle is now pulsing alot more, its pretty bad actually, Im using 5500 as the scaler. I believe this is what I used before its been about 2 years since I messed with the LS4 but I know it was about perfect before I'm trying to figure out what it is that I've done differently this time I have almost 4 years of logs and tunes from prior experiements and setups over the years so its not easy to find.

I have my .hpt file and log if it makes it easier for someone to see what I've left out

 

zzp has the how to on their website: http://www.zzperformance.com/
Here:

**PCM calibration required. In HPT under engine idle airflow the ETC area scaler is normally 2950 (this works out to throttle plate area in milimeters less the rod area).

67.4 dia, pi*r2 = 3568 less throttle rod area (620) = 2948

75 dia, pi*r2 = 4418 less throttle rod area (730) = 3688

You'll need to change the 2950 to 3688. Many users have reported better results going even higher. We have tested numbers ranging from 3775 to 5500 without issue.

 

yea ive saw that before but the scaler is not whats causing my issues

 

jw how touchy is the ls4?

 

You can tune it to be not that bad, yea it takes some getting used to and it certain situations or weather conditions its not suitable

Like during winter I take it off, car is naturally a bit more powerful with the colder air, just becomes uncontrollable in something like snow.

 

surging, sounds like you might have leak around your sensor in your intake.

 

Maf sensor?

 

Right before my maf went out it would do the samething your talking about. For about 2 or 3 years it would always idle weird and when it would rain I couldn't drive my car because the rpm would shot up to 3k and drop to 500 and shot right back up and etc... but come to find out that our maf is in a shity spot.

 

I'm going to experiment with some things here in the next few days but my Maf is clean as new, not even a spec of dirt on it

 

What did you use to clean it?

 

didnt need to its perfectly clean, ive always been careful with keeping the filter good and not exposed to water

 

I just bought a tvs and am going to put it on this weekend. I was told not to mess with the ls4 due to tuning and drivability nightmares. Y'all agree?

 

Nope. My balt is doing great and not a hint of throttle touchiness. Using 3688 as the scalar and the stickied 60# values for my injectors listed in this very Tuning section.

Got mine from ZZP, they machine theirs in a mill so it is modified specifically for us cobalts.

Thus far, zero issues.