rich cruising and idle

[blown383z28]

Hi guys, Im kind of new to the tuning world so bare with me. I got a 99 gs. 130k miles. All stock but a cold air intake, 3in down pipe no cat or res.. Tuning with hp beta. Im all done tuning ltft's. all are with in 0-5. the car has never got the best mpg. i now have a wide band hooked up for wot tuning. Idle closed loop its about 12.5 and the same cruising... I have tried recalibrating and two different sensors. all settings are right. I put it on another car and it ran 14.5-14.7 the hole time. I am now thinking it is the car... Y would it be so off..?? wot it is about 10-10.5...
I got a short log at idle and my latest tune. any help would be great!!!

[blown383z28]

No one???????

[GeoJB]

Do you have Gary's tuning guide?
He was a "Jedi master" with these 3.8's.
If not PM me.
Or stop over to RegalGS.org. A copy of his guide is in the How to section.

[GeoJB]

You need to set up a MAF histo.
that will help you clean up your tune.
These cars like to use the MAF first. then refer to the VE... I'll say for "checks & balance".
If the MAF fails, the VE takes over.

[BlackGS]

Have you reset trims recently? If you reset trims, how much did you log after that? You should make sure to log a good 20-30 minute cruise to get correct data for trims, and don't log right after filling up.

If we make the assumption that the wideband is reporting correctly at 12.5, then either there is not enough trim data, or the narrowband would have to be messed up because there is no way you would have trims that close to zero with 12.5 afr in closed loop. However, I think the narrowband is working ok because it is sweeping correctly and you have been tuning trims, which look to be in line. Even though the wideband is reporting correctly on other vehicles, it still may be in a bad location, or not functioning as intended on this car. Do you see the wideband sweep up and down from richer to leaner while observing it? In closed loop, you should not see a steady AFR. The AFR will oscillate up and down. If the wideband is not moving up and down like this, then it would strengthen the assertion that the wideband is faulty. From your short scan, the wideband looks fairly steady even though the narrowband is sweeping. In my car under closed loop the wideband will sweep along with the narrowband, usually in the range of 13-16afr.

Don't touch the VE, it's pointless for this problem (and for tuning most 3800's in general).

Go for a long drive and post a scan if you get a chance.

[mdberger11]

Do you have a o2 spoof?

I run no cat and without my spoof, the car will sit at 11.0 - 12.5 AFR for two minutes upon start up while cruising at 45 MPH+. Some kind of catalytic efficiency test. Try running a spoof.

[blown383z28]

I have no idea what your talking about.. could you explain more? I have 3in down pipe wth no cat or resonator.. i shut off the lights for the rear o2's..

[BlackGS]

PCM will command richer AFR to protect a faulty cat. Add Commanded AFR to your scan data to determine if that is the reason for the rich condition.

[blown383z28]

i looked for that.. i didnt see it.. where is it in?? thanks!!

if it is how do i stop it?? what to change?

[blown383z28]

any one walk me through how to get the command afr on the scan. I thought i had it but is says unsapported.. i have the newist beta..

[REDNECKRACING]

try this setup. might need some fixing (the boost) it is the one i use non bata. but it will work for bata. (except the boost i think)