Just Checking

[twpetry]

Ok so i started tuning the car today just want to post up the info and have you guys check it out, make sure i'm on the right track.

Car is a '99 Trans Am A4 basically full bolt-on. Predator is a U7198 revision 2.13 with the performance tune installed

Ok so i started checking LTFTs i tried to keep the trips consistent around 20-30 mins or so, about 55-65mph, and 9-13% throttle, rpms around 1800. and came up with about 3.91% & 4.69% so i pulled 5% injector slope, drove out again and numbers were better like around 1.56% and .78% so i pulled another 1% injector slope, drove again, pulled another 1%. and ended up with about -1.53% and -2.13% LTFT with -7% injector slope, which i'm assuming is right on the money? but that was mostly open road driving when we got stuck behind other cars, and had to constantly change throttle position, the LTFTs jumped way down like -5% -7% so i should probably add a percent or two to the Injector slope? I was pissed because i thought i had it dialed in.

Also at WOT i'm getting 3.96* of knock retard. i'm kinda confused about the spark timing and such, i mean spark is reading like low 30*s i thought that was way too high? i think i pulled about 3% spark from 2k-7k but the knock didn't change. i'll be tuning again tomorrow so any help would be greatly appreciated.

[ches111]

If you are constantly changing throttle position you will see changes in the LTFTs ...

So your info at 1800 or so should be good. Be sure to be a little over 1800 so your LTFTs are dialed in at cruise.. You can drop a gear if need be.

2K I think is the preferrable area.. however 1800 - 2500 should work..

So far looks like you are right on..

Is the KR at WOT throughout the WOT or just at tip in?

If it is at tip in and does not continue past tip in you are ok.. You should see a little when you get off of it as well.

[twpetry]

yeah the KR is continuous during WOT runs

[06MonteSS]

did you drive for 30-50 miles before checking data again after the slope changes??

it usually takes that amount of mileage before the fuel trims get relearned by the PCM and be accurate...

if you did, and your average LTFT's were -1.53% and -2.13% with a -7% injector slope setting, I would bump that up +1% and make your injector slope be -6%.

that should put your average LTFT's right around -0.53 and -1.13...

[concoursd]

also, look at adding some fuel at WOT rather than pulling timing. WOT fuel adjustments are best when verified by a wideband o2 sensor. You may be running too lean at WOT. I would also get a good datalog before making anymore LTFT adjustments. Try to get it more near 0 though. I think that last 1% drop may have been too much but this depends on the accuracy of your datalog.

[twpetry]

Just a little update, i spent most of yesterday tuning for WOT. I'm still getting 4* of KR, but come to find out its throwing Knock Sensor Low Input codes at me, which apparently means they need to be replaced and automatically triggers the 4* KR upon WOT. So i guess i need to replace those. Also i'm trying to get a baseline 02 reading down, right now i'm between 910-925mv i was under the impression i need to be around 900mv. I know that narrowbands aren't accurate but i'm trying to at least get a decent baseline tune, before i take it to the dyno. The car is popping/sputtering/backfiring at WOT i'm guessing thats a combination of KR, rich a/f, and i have a very free flowing exhaust. i think i pulled -4% PE from 2-7k but like i said that got me to around 910-925mv. I'll probably pull a few more %'s before i actually get it dyno'd and really see my a/f. thoughts anyone?