LTFT's and STFT's?!?!?!?!?

[hcbr929rr2]

So I installed my Cobb Sri last weekend and have been monitoring everything to make sure nothing crazy is going on, and here is my dilemma.

My LTFT's are anywhere from +7 to +17??? but afr is fine if not a bit rich, fuel rail pressure is fine, even STFT's under wide open throttle are at 0.0, all connections are tight, no leaks, stock bpv, any thoughts? I am in Denver so being a mile high will mess with cars a bit but I'm fairly confused here, why would my LTFT's be so far off if my STFT's are ok?

 

[ZPrice]

I saw this post on MSF, I believe they gave you some answers (get Abilors guide, get an AP, install ATR, read ATR help file). Don't worry about the short terms for now, the issue is to get the long terms down below 4 and below 2 if you can. First install the proper map based on your mods, drive around, perform some MAF calibrations, do some math and adjust the proper table, reflash to ECU, drive around, perform some MAF calibrations, do some math and adjust the proper table, reflash to ECU, repeat until LTFT are resonable. You don't use the fuel trims during WOT, you use the AFR measured versus AFR requested to make adjustments to that portion of the MAF table.

You might want to make sure you don't have any air leaks, I did not make any adjustments for a year with only an intake modification.

Z

 

[hcbr929rr2]

yeah I dont have an AP yet, I plan on getting one in about 2 weeks, I was just concerned when I saw this, checked for air leaks, nothing, I just don't understand if my STFT's are at dead 0 under WOT why would LTFT be so out of whack, I read through his tuning guide, amazing information I will definitly be using that when I get my AP, until then though, I just don't know if its safe to keep driving around with my LTFT's at 17.2

 

[hcbr929rr2]

ugh, now I went to lunch and I'm up to 18%, I don't understand though cause STFT never went past +8.6% to -8.6% think I should just reinstall stock til my AP, or could reseting the ECU be worth a try?

 

[ZPrice]

Temperature variations will cause issues with FT. Is it possible that you got something on the MAF sensor when you installed the SRI. Also, check the electrical connection, something is wacked. Are you sure you are getting the proper numbers?

 

[hcbr929rr2]

well on my way home I spiked to 19.5% LTFT so that was enough for me to swap back to stock for now, fuel pressure was spiking at over 1800 then settling at around 1700-1750, my afr was pretty consistant at 11.8 to 1 at WOT, I went back to stock and the funny part is the only things that changed are afr (is now back to 10.6 to 1) and LTFT is now -7ish at idle and +6.2 at WOT, the STFT, Ignition advance, boost, and fuel pressure are all pretty much exactly the same, granted I only have about 5 miles logged after going back to stock but I'm guessing it should all stay pretty consistant, I'm confused lol

 

[himurax13]

Hot weather can increase the LTFT's a bit. According to COBB + or - 8 is acceptable but I like + or -2 myself. Did you reset the ECU after uninstalling the SRI?