VE tuning??
VE tuning?? I have started tuning the VE tables on my 98. So I followed the directions about unplugging the MAF and scanning the car, etc....My question is this:The first time I scanned the car, it seems that it was very close to being correct like it was. I mean for the most part, the LTFT's were all between -5 and +5 without having done any tuning to it. Is this pretty common or am I just doing something wrong? I followed the directions pretty accurately...it just seems weird that they are already that close. Also, my other question is this...once I make changes to the LTFTs and reset the fuel trims, do I have to drive the car for 50 minutes or so to have the computer learn the new changes before I scan again or can I just load the new changes and begin to scan immediately??
I tried to get some help in this area but no one really could give me much. I was also very surprised that unplugging the MAF yielded such decent results. My fuel trims were for the most part 128 (I use LT1 Edit, looks like you have Tuner Cat or something) so they were dead on. Only problem was my O2 voltage would drop on the right and cause my BLM's to spike to as high as 161 (I guess +33 in Tuner Cat) during deceleration. No one could explain that. It idled bad in open loop and still had some rough spots in closed but I thought I was getting somewhere. I finally gave up on speed density when Ed Wright said he only got 6 hp or so out of a max effort. I think the VE tables are *mostly* useless in MAF mode, so if you plan on staying MAF I wouldn't worry about it. If you are going speed density, I would go back to MAF. Just my experience. 
I have HPTuners and I was going by a tuning guide that I printed off. It says to get the VE tables and MAF stuff as close as possible in SD and then once they are close plug the MAF back in and everything should be good. It was a little rich down low but not as bad as I figured it would be
Originally Posted by TN94Z
I have started tuning the VE tables on my 98. So I followed the directions about unplugging the MAF and scanning the car, etc....My question is this:The first time I scanned the car, it seems that it was very close to being correct like it was. I mean for the most part, the LTFT's were all between -5 and +5 without having done any tuning to it. Is this pretty common or am I just doing something wrong? I followed the directions pretty accurately...it just seems weird that they are already that close. Also, my other question is this...once I make changes to the LTFTs and reset the fuel trims, do I have to drive the car for 50 minutes or so to have the computer learn the new changes before I scan again or can I just load the new changes and begin to scan immediately??
Depending on the modifications, you may not be that far off. Once you modify your SECONDARY VE table give the car a good 45 minutes of varied driving before you start logging for FT's again. It takes ~20 seconds of consistant load for a cell to stabilize and learn it's correction factor, hence the 45 minutes of varied driving.
