VE tuning question

[futuretech]

I am running in open loop (per 69tbird). I have made several 10 mi expressway runs with slow accell and decel. I then adust the VE table with using the scan data. Example: I will multiply a cell that cell which displays 5.x with a correction of .95. Did this to most cell with a > 2% variance.

However the next scan shows different cells off by 5% or more that were fine on the previous one. The cells I corrected are right on or way off too. No pattern. Am I doing something wrong? I am using the stock afr ratio error on hp tuners and my afr on logworks shows the same as hp.

[mcbusa]

log your short term and long term trims to make sure you are truly in open loop and reset them too if needed so there is nothing that can be lingering, and if it is 5% off don't multiply by 5%... multiply by a little less you don't want to overshoot and chase your tail. and also make sure how many hits your getting is significant like have 50 for the counts in the histograms so you are getting good data and make sure you are using the average and not last or min or max.

[futuretech]

log your short term and long term trims to make sure you are truly in open loop and reset them too if needed so there is nothing that can be lingering, and if it is 5% off don't multiply by 5%... multiply by a little less you don't want to overshoot and chase your tail. and also make sure how many hits your getting is significant like have 50 for the counts in the histograms so you are getting good data and make sure you are using the average and not last or min or max.

Thank you

[mild7]

Try to do the logging at same temperature every time.

[futuretech]

Try to do the logging at same temperature every time.

AHA! Ten points for mentioning temperature. I usually do it over several days.

Do the trims make the adjustments for weather in closed mode?

[tpcaz]

If you are using a MAF and in closed loop.