Quote from another post....""Once you have all the cells hit at least 20 times copy and paste by % error into the VE table. Start the car up again and restart the process. Drive around on the open highway again for about 5 mins before starting to log again. The reason for this is when you shut the car off to flash the new tune the car heatsoaks. This will throw off the tune. Driving around for the 5 mins just gets rid of the heatsoak. Now when you copy and paste by % error into the VE table you should have less error than last time. Now as you get closer to 0% error you should see that the WB gauge is closer and closer to 14.7 at part throttle driving. When you now paste the error in the VE table paste by % error half option. This just prevents you from going to far and overshooting the error. you will never get to 0% error so dont bother wasting your time. you should be able to get +-4 though.""




my question..was reading a post (quote from above) about VE Tuning in Open loop. Now I understand how to put the car into open loop, and that it's neseccary to tune the vehicle in open loop. Now after you log the run and see what cells need to be adjusted for fuel......where is says to copy and paste the % error into the VE table....what values do you get the percentages from, and how do you alter the readings in the cells in the VE tables to adjust for more or less fuel??? Also, after tuning the vehicle do you leave the car with closed loop disabled, or do you enable it again???

 

The values that are logged while tuning in open loop with a wideband is "AFR error". The values you copy into the tune is the percentage difference between what the commanded fueling number is now and what the actual should be, calculcated by comparing commanded AFR in that cell and actual AFR reading from your wideband. This will leave you with a table of errors for each cell. This is then copied into your tune and in a perfect world will bring your actual AFR right to where you command it.

After you are done tuning, yes you would normally renable closed loop. The time you wouldn't is when you would then proceed to tune your MAF in open loop using a wideband.

 

awesome....so I would be able to use the afr error histogram that they have already in the main tables to get those values from???

thanks for helpin me out


+ rep. given

 

I'm used to just making my own histogram for whatever I'm doing at the time so I'm not sure offhand what ones are offered preconfigured. To set up one for VE you should only have to set one axis up for the table value "Primary VE vs. RPM vs. MAP" and the other axis will automatically fill in the same value. The PID you want to plot on the histogram is "AFR error" I believe. Make sure AFR error is being logged as well as your wideband and "commanded AFR" in the PID list.

 

ok awesome....I'll give that a shot....then on to MAF tuning hahaha. I appreciate the help

 

No problem. A couple of other things while I'm thinking of it....don't stress too hard on VE, its only a backup in case of MAF failure, something you probably won't ever need. Its also used for the car's own throttle tests to ensure the electronic throttle is working which is why this must be done. I usually dial in VE somewhat close and then just highlight the whole table and smooth it twice and it comes out pretty decent.

When you start on the MAF its 5x easier and faster because you have a lot less values to deal with since you're calibrating a sensor thats measuring actual airflow. MAF should be dialed in as good as you can get it. The more accurate you can make it, the smoother your AFR will be.

 

excellent, any tips on tuning/dialin in the maf you can share?

 

Its basically the same as doing VE, just with less values really. The only thing I would recommend is not to use the smoothing function in HPT while calibrating the MAF. If you have to, hand smooth. Using their smoothing feature when MAF tuning will throw the entire calibration for a rollercoaster ride.

 

so pretty much for the maf tuning....I would take the afr error % copy and paste it into the maf cell, just like the VE tuning?? Just no smoothing after....

 

Thats about it.