UnZFeat'd

iTrader: (1)

Also, i believe i remember the LTFTs being like this even before i cut and spliced the wires on the o2 sensors. What could be causing my car to do such erratic things with the fueling? Thanks

JonCR96Z

iTrader: (33)

I've never had any personal experience with them, just heard a few stories. Maybe not even have been all the O2s fault.

As far as the O2s being your problem just disable closed loop. Either in the tune or with the bidirectional controls in the scanner. It your problem goes away then more than likely the O2s are the problem.

UnZFeat'd

iTrader: (1)

Here is what i got from it today... also uploaded my tune that i had in case you guys have anything to say about it. Thanks

Frost

iTrader: (45)

Your MAF ouput looks pretty low.

Borrow a buddy's to check it out. Once you swap it, go ahead and reset the fuel trims through the VCM controls in your scanner and let it re-learn from there.

Frost

iTrader: (45)

Alternately, you can try this:

Unplug your MAF. Turn your key to RUN, start scanner and use the VCM controls to reset fuel trims before starting the car. Drive and log. This is SD, and if the trims look good running like this...

UnZFeat'd

iTrader: (1)

ok, here is a log of my tune without the MAF connected. We reset the fuel trims and drove it around for a bit.

Frost

iTrader: (45)

There you go. That log is only 9 seconds but LTFTs + STFTs = about 4%.

Your 'ported' MAF was really a ruined MAF

I bet it drives and feels much better in SD right now

UnZFeat'd

iTrader: (1)

What does SD mean? Here is a longer log that i did today on the freeway with a couple WOT pulls

Frost

iTrader: (45)

If you look at these logs and notice that the histograms look screwed up, it is because the MAF is being logged and the histos are using them for their dynamic airflow measurement. That's a problem with no MAF.

UnZFeat'd - Leave the dynamic cylinder air in the table view of your scanner, but remove Mass Air Flow (SAE) and the histograms will populate correctly. They are not usable (to copy paste into the editing file) like this. To answer your question, SD is speed density. How does the car feel?

Also, your largest LTFT is less than 5%, so the MAF was definitely the problem.

It's time to tune for those boltons, it's rich and has stock timing at WOT.

UnZFeat'd

iTrader: (1)

t has tock timing right now because i plan to run nitrous in it. Right now it is jetted for a 75 shot, but i plan to go up to a 150 shot if the tune will help me do it. It felt a lot better without the MAF. There was no hesitation at all, and it didn't want to die on idle.

UnZFeat'd

iTrader: (1)

Here is a new log with a new MAF that i did today. Please let me know if you see anything out of the ordinary that i should change

Frost

iTrader: (45)

trims are maxed out towards the end, looks like the same MAF!

UnZFeat'd

iTrader: (1)

ya, but this is a brand new one. I just dont understand why it would be like this

Frost

iTrader: (45)

by brand new do you mean GM or do you mean Autozone?

UnZFeat'd

iTrader: (1)

well i mean autozone... but it has the screen and airfoils. It should be the same thing, right?

Frost

iTrader: (45)

haha... sorry.

Tune it, but there is decent chance that thing will be inconsistent and you will chase your tail some. They are never the same thing as OEM parts for whatever reason, they are kind of all over the place from my experience.