2000 4.3 Stft Ltft tuning

[tiresmokinV8]

Ive found how to do it before I had HPTuners but now that I have it I cant seem to find the step by step procedure. I know I reset the fuel trims and tune to get the stft and ltft to add to 0. BUt thats all that I remember I have a wb so I think there was something about using it while loging to help with this tuning. And is this a part of MAF tuning or VE?
Thanks Im such a noob.

[oakleafresin]

Follow this guide bro, it should be pretty much the same for you having a 4.3.
http://www.hollandms.com/newbie/tuning_new.htm
Basically you disable your MAF and tune your LTFT's as close to 0 as possible by modifying your VE table. Then you re-enable your MAF and calibrate the MAF table till you get 0's again. Do the MAF table with your WB since you have it though.

[tiresmokinV8]

Thanks Itll help tramendously

[Russ K]

Leave the VE table stock, tune the Maf table only. Put the truck in open loop, and use the wideband.

Russ Kemp

[tiresmokinV8]

Why am I leaving the VE table stock instead of zeroing it and then seroing it again with the MAF?

[Russ K]

The VE table is only used when there is a Maf DTC. Failing the Maf & tuning the VE table, then enabling the Maf & tuning the Maf table will not change the AFR compared to just leaving the VE table stock and tuning the Maf only. You will only frustrate yourself tuning the VE table and won't gain any performance gain.

I've done SD tunes when the Maf is removed for less intake restriction on high powered (500 hp) cars. But the Maf isn't a restriction on a 4.3 V6.

BTW, I noticed that you set the PE to 1.5 (9.8 AFR) on post #3 in the V8 Trans section. I said to set it to 1.13 (13.0 AFR).

Russ Kemp

[tiresmokinV8]

Yea I know and I did set the pe eq ratio vs rpm table to 1.13 but maf must be way out of wack or something because with that. I would hit 14.5+ afr on the wb. I kept bumping it up to 1.5 and now its 12.8 at wot I just did this temporarily until whatever is out of wack gets calibrated. Im sure my wb is accurate and the truck definately without a doubt pulls way harder now then when it was 1.2 on the stock wait4me tune.

I wasnt ignoring your suggestion.

Ill just tune the Maf this weekend with your config you sent me.

[Russ K]

I've seen a lot of bad maf sensors causing lean AFR's. If the fuel trims are high (+15%) in closed loop, the Maf needs to be replaced. Sometimes the Maf can be cleaned by spraying carb cleaner on the Maf sensor hot wires.

Post a closed loop scan log with my config file, drive around at part throttle & moderate acceleration.

Russ Kemp

[tiresmokinV8]

Will do it may be a few days tho since right now Between work and college everyday its 14hr days. This weekend would be the soonest Id be able to get to it.

[nick13618]

when i'm watching the ltft table, am i watching the average, the last or the highest value in the histogram? Is there a way to get the ltft table from the pcm?