BlackGMC

iTrader: (31)

Edit: the title should say Open Loop not SD....


Well I got my VE table dialed in with in 1% so I decided to reenable my MAF to tune it via BEN correction. Everytime I would take my foot off the gas it would go way lean (18+) in the lower MAF Hz ranges. I would apply the BEN correction and it reflash then it would do the exact same thing. I have done this same process before my headers and new exhaust setup. I also put my WB after the Y pipe so it is farther down stream, previously it was next to the first factory O2 sensor... I don't think I have any exhaust leaks, do you think the placement of the WB is the problem? Attached is my tune and loggs.

AutoVE-002_0003 = MAF Disabled, AutoVE tune
AutoVE-002_0004 = MAF Enabled

Log_0003 = MAF Enabled Log...

Any help would be great!!!!

03sierraslt

iTrader: (22)

Well I cant view your logs but do you have DFCO disabled?

BlackGMC

iTrader: (31)

Yep DFCO temp enable was set to 252... The wierd thing is it only does it when the MAF is enabled in Open Loop. In Closed loop or Open Loop w/ MAF disabled it does not do it.....

BlackGMC

iTrader: (31)

Anyone? Bueller.... Bueller....

03sierraslt

iTrader: (22)

In what MAF Hz is it starting to go lean? What MAF Hz does it idle at?

BlackGMC

iTrader: (31)

Between 2375 and 4000. For example, It will idle just fine not problems, a little lean or a little rich, then I go drive same thing a little lean or a little rich, as to be expected from an untuned MAF table. But when I am at speed say 60 and I left off the throttle complete and let it coast or I hit the brakes the AFR goes to 18+. then after a little bit it will return to normal....

One thing I did read is that ram air may cause this. I have a ram air tube in the tow hook position and the other end is pointed directly at the MAF (stock air box with K&N)...

03sierraslt

iTrader: (22)

Personally I would move the wideband closer (Mainly for acuracy and proper heating)but at the same time I can't say thats the problem. What does your timing do when this happens? Its been awhile since I messed with MAF tuning.

BlackGMC

iTrader: (31)

Well I am going to try something different that DC_Justin suggested that I finally got to work. I am going to log DynAir while OpenLoop no MAF and get the MAF values. I tried it early but, I did not have the column width wide enought to see that the hundreth or tenths digit, (I know I am retarded) so I thought I was only getting single digits.... I will report back my findings...