Idle is much improved. I kicked the tune up another level and all is well. Still not sure why it was needed, but it doesn't matter at this point. Its near perfect now.

WOT the truck feels great in this crisp winter air. I logged a 0-90mph run today in 7.7 seconds. I think that should be good for low/mid 12s in the quarter.

On to the next problem I have... To much air and not enough fuel.

My MAF hits the limit between 4800-5300 depending on outside temps. In the cool 35* air outside today, it hit 60 pounds around 5000 rpms.

I'm out of injector. According to my EFI logs, my pulse widths hit 23ms by mid 5000rpms. I increased my fuel values with this latest tune, but the O2s aren't responding. My O2s dipped under .800 by 6200 rpms tonight. Looks like I'm going to need to lay off of it until I make a fuel system change. I really didn't want to have to do that so soon.

Truck has always been nice to drive, but the fun factor has gone up considerably in the last couple of weeks.

 

Tex, PMS!

 

Is it safe to say you are happy with it?

Congrats on the troubleshooting.

 

Opps not PMS, but PM's

 

Oh yeah, I'm pretty happy. Sorry for not saying whhheeeeeeeeee in every one of my posts, but I do like the sound.

I'm going to mess with the fueling a little over the weekend and see if I can get by with it for now. I'll need new injectors at some point, but I don't want to rush into it. I'll bring my shifts down to a safe level for a while.


What is the downside to increasing fuel pressure to say 65-70psi over the stock 58? Not just at WOT like a FMU, but all the time.

 

are you maxing out the 42lb injectors?

Do you have a spec sheet on all your mods?

wheeeeeeeee!

there's one for ya bro

 

Have you added fuel to the top end where you're maxing your MAF to compensate? Thats what I did, and it seems to be working OK last time I checked.

BTW, HPT has a 3 bar SD tune coming out to use on the stock PCM. I think that's going to be very beneficial to us FI guys.

 

Hey Flyer, I was reading about that 3 bar tuning in the FI section and HPTuners forum -it's going to be pretty freakin' sweet

BigTex, so what did you tune? Did you get rid of the slowing down stalling? How? Spill the beans man!

whhheeeee

 

Yeah, I added fuel w/ PE, but its not helping. At 6400 rpms, I've got a 1.5xxx value. I need to get a fuel pressure gauge hooked up. That will be the next item on my list.

Idle tuning - I bumped up running airflow another point or two in the higher temps. I added just a bit more IAC. On the cracker table, I added a value of 1.0 to the 0-36mph@400rpm cells and the 0-4mph@1000rpm cells. Idle is still set for 800 rpms. It doesn't stumble anymore and doesn't have any cruise control effect, so I think I'm pretty close. VE is stock.

I heard the HPT won't go live for several months with the 3bar SD tuning. I don't think I'd need anything over 2bar anyway. parish8 could use the 3bar though. In reality, I'd prefer to stick with the MAF simply for the daily driver aspects. I never intended to really take this truck to the limits. I wanted a strong tame well mannered truck. I've got that now and would like to keep it that way.

 

Right On! Hey do this quick test for perfection. Take the revs to just before a shift into second gear. Don't actually hit the shift to second gear but go right before it really wants to shift. Then hit the brakes Hard. Did it stay alive?
If so, you nailed it! You da man