Help me understand this scan please

[Moonbiter]

Please help me understand this scan from my car. From the little knowledge I have in tuning, it appears I have a fuel trim problem.

Car background:
2002 Grand Prix GTP
160* tstat
SSIC
3.2 pulley
Autolite 104's
Wiz air intake
DHP pcm (not generic)

I do not have a Wideband yet (can't afford it yet) so I have to do everything with the trims and O2 sensor. The file I have is a 0-60. The cruising one was to big to upload, but the trims on that one are pretty bad also. My typical LTFT is between 3-9 normal just cruising around.

Could someone please give me a direction to look at on how to go about correcting this problem? I've read this sitehttp://www2.turbov6camaro.com:81/tune.htm and still don't understand everything going on regarding fuel and afr and how to bump to table and where to bump it.

I'm pretty lost right now, and I think I've read so much that I'm just confusing myself more. Can someone give me a nudge?

I know I have a lot of tuning to do now that I've looked at a scan and I'm just lost on where to begin.

Thanks.

[Junior1683]

your really really lean, which is very bad (thats how people pop pistons and what not). your in the same boat as me when it comes to tuning your fuel trims. id start there.

[Moonbiter]

Ok, I'm lean because my LTFT is adding fuel. So, the engine is lean, but at WOT the O2 seems to be in the right area. Is this because the PCM is making up for the lean condition? If I change my LTFT (adding more fuel) so the trim is closer to 0 or a negative number, is this going to change the O2 reading saying I'm rich, or is just going stay about the same, but the car won't be adding fuel to a lean setting?

According to this site: http://www2.turbov6camaro.com:81/fuel.htm I need to play with PE Add vs RPM table. How do I figure out what cells to manipulate? Do I need to get some good scans together? Also, on the PE add vs RPM table Engine speed is easy to figure out, but what is the Y axis "sec" coming from?

[Hauss]

you are only really lean at idle(unless I missed something) , and kinda lean above idle. you won't ruin any pistons at idle.... tune the maf with the ltft's .your maf is reporting the incorrect airflow because of the CAI..

[Bill@HPTuners]

You can't say he's lean or rich without a wideband. Just because the computer is compensating by 16%, in fact he could be running rich, but theres no way to tell without a wideband really. More than likely though he's hovering at 14.6-14.8:1 where he should be...the pcm is just compensating.

[Moonbiter]

Ok, but what I need to do though, is adjust my PE table so the LTFT is closer to 0 correct?

Also, do I need to redo my MAF for the airbox?

[Bill@HPTuners]

PE is mainly wot fueling, and usually won't come into play at part throttle/steady state.

[Moonbiter]

Ok, so what do I need to adjust then, the MAF table?

[JFDugal]

Before you start digging into the tune, check & double check for any vac leaks. Short stack intercoolers seems to be more prone to sealing issues than others.

Once you're sure there's no mechanical issues, a MAF tune would be used to get your trims back in line.

BTW, you should add MAF Frequency (Hz) and Injector Pulse Width. Commanded AFR couldn't hurt either (good later for PE/WOT tuning).

[Moonbiter]

I'm pretty certain I don't have a vac leak. The boost pressure runs about where it should, and my trims look about the same before and after the SSIC install.