im working on my first tune from scratch. i got it into SD and everything by following the HPT writeup. now most of my cells that are center area of the histogram are +/- 1 or 2%. but when i downshift all the cells along the top of the histogram wont fall into place and i have been working on this for a couple of weeks now. also the cells in the 400 and 800 rpm column dont want to fall into place either. if you guys could look over my log and tune and give me some pointers i would appreciate it.

 

You have everything right except your VE table looks like mount everest and you have power enrichment enabled. I made some changes to your tune and and renamed it accordingly. Use your compare feature in HPT to compare your tune vs. the one I modified for you. Once you see and understand fully what I did, flash the tune I gave you in and take 'er for a spin. I also fixed your timing in your idle spark advance cells. That truck must idle like turd with only 9 - 16 degrees of timing. If your STFT's all fall within an acceptable limit, get back to me. I'll fix you up with a revised timing table and good PE settings

 

You'll see some other tweaks as well like me zero-ing out your MAF table just to make sure and disabling your PE altogether. Now go burn some tires and report back!

 

Why would you zero out the MAF table?

 

Because he's trying to dial in his VE table. Although he has his maf fail set to zero HZ, this ensures that the MAF will NOT WORK until he's ready for it to do so. It's just an extra safeguard in place, that's all. If you look at his tune, you'll see I put several things in place in his PE area so that he will not enter PE until he's ready to do so. It's redundant I know but it's good practice.

 

Yep sounds like a good idea. Just another way to do it... When I tune the VE table with trims I leave PE alone and just filter out all commanded AFR not equal to 14.68...

 

thanks for the help guys. i did have the pe disabled, but according to the hpt writeup you dont do that. i had just turned that on bout a week ago. again thanks for the help and ill let you know how it comes out. on a side note the truck idled great. sounded like an old muscle car. ill take a vid before i reflash.

 

Eh you think it idled great That's hard on your motor mounts, exhaust, engine (excessive heat) when it's not combusting properly. Trust me, you'll like the smoother idle. Start your truck up, open the scanner, enable the fixed timing button and move it up and down. You'll see your idle quality get better and worse.

 

Try the new tune, I bet you notice a huge difference in throttle response and idle quality. Also your return to idle quality should improve as well.

 

yeah your right it always has "huck upped" when returning to idle. so my lack of ever having a good tune makes me still thing that i have a good tune, lol. i got bout 45 mins before i can play with it, i cant wait. thanks again hidlej.