Rich during MAF Tuning

Hello, I am tuning MAF tuning, I believe I turned off all the required things such as LTFT and STFT, COT. I started tuning and the scans keep saying its on the rich side, I keep modifying the MAF Calibration, but it doesn't seem to help. and my WB does show at idle it even drops to 13.0afr. I currently have my stoich set to 14.22, but this wall still acting this way even when stoich was 14.68. Any idea why? Does this look like a vacuum leak or perhaps a dirty maf sensor? I would go check, but it is currently raining cats and dogs, so I am turning to the forum for help. thanks.

Here are some quick logs, with a 30% difference between the maf cal, and the scans still shows somewhat similar results.

2000 Silverado 5.3Vortec. mods: cold air intake and larger TB.

Need to know what it is we're looking at. Complete list of mods.

And stop trying to tune part throttle with a wideband. Turn your trims back on and use them. Disconnect your wideband until you're ready for WOT tuning.

Updated vehicle info.

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Originally Posted by rgarza38

Hello, I am tuning MAF tuning, I believe I turned off all the required things such as LTFT and STFT, COT. I started tuning and the scans keep saying its on the rich side, I keep modifying the MAF Calibration, but it doesn't seem to help. and my WB does show at idle it even drops to 13.0afr. I currently have my stoich set to 14.22, but this wall still acting this way even when stoich was 14.68. Any idea why? Does this look like a vacuum leak or perhaps a dirty maf sensor? I would go check, but it is currently raining cats and dogs, so I am turning to the forum for help. thanks.

Here are some quick logs, with a 30% difference between the maf cal, and the scans still shows somewhat similar results.

2000 Silverado 5.3Vortec. mods: cold air intake and larger TB.

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use your fuel trims to dial this in.

Also.. you need to change your wideband to lambda or eq. It is setup for gas.. So perfect stoich is going to be 14.7ish. You set the PCM up as 14.22.. so if this was tuned perfectly in a ideal world your wideband would read 14.7 and your PCM would read 14.22.

Things get a lot simpler if you use EQ or lamnda instead.

STFT or LTFT? Or both?

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Originally Posted by rgarza38

STFT or LTFT? Or both?

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You can use just STFT. I like to use LTFT+STFT, it seems to give a better result with a mostly stock setup, IMO. Once its in PE or at WOT then the wideband comes into play.

Ok, so STFTs are enabled. I changed the stoich back to 14.68, and changed my wb output to lambda. How does this one look. Which graph should I be using? EQ ratio error/maf freq