WS6FirebirdTA00

iTrader: (33)

ok so when i got on the gas i was in FTC 14 and all the trims were 0, then i hit FTC 15 then 22, as soon as i went into 22, the fuel trims went to +8. its a pain in the *** cause i can definately tell they go positive cause the car feels way down on power. why in the hell does it do this? sometimes i can go out there and i have no problems and now they are +, i dont know if its cause the car has a new tune in it and it needs some more drive time or what, but its frustrating

JNorris

iTrader: (4)

I feel your pain.

WS6FirebirdTA00

iTrader: (33)

again today, WOT in 1st and it was fine, then i hit 2nd and it was all fine, then traction came on and when i was able to go wot again +2.3,+4.7. yesterday after a trim reset it wasnt too bad. i feel it has something to do with the startup cells being in FTC 20-22 and going lean and then getting ok. hopefully its something that learn time will straiten out. its a big PITA

WS6FirebirdTA00

iTrader: (33)

looks like as soon as i put the clutch in on one of the runs, it went to those numbers. i put the clutch in, rpms went up a little then all of a sudden the trims were +. next step, open loop SD tune, if i cant fix this BS

SSpdDmon

iTrader: (10)

Did you change your fuel trim cell boundaries?

WS6FirebirdTA00

iTrader: (33)

yes, i did. i believe they are set to 30,57,75 kpa and 1200,2400,4000 rpm. how does that look? could those values be giving me trouble?

WS6FirebirdTA00

iTrader: (33)

also, i get those + trims AS SOON AS i hit FTC 22, wont do it in 14 or 15

SSpdDmon

iTrader: (10)

If your tune is spot on in closed-loop, I'd try putting your FT cells back to stock and see if it still does it. The way they're set up stock, it looks like some of the cells are disabled (specifically 2,3,6,7,10,11,14, and 15) given they are for >6500rpm. I believe the computer adds +LTFT's at WOT based on the trims in cells 12 & 13 and maybe 8 & 9.

As for the positive trims during warm-up....cell 20 is for cold idle, cell 21 for deceleration, and 22 I believe is a dump cell of all other conditions during warm-up. If you're seeing positive trims here and not in warm closed-loop, I'd question how fast your O2's are heating up and possibly delay or discredit the information they are reporting until they are warmed up more. I think this could be where your real problem lies. If the computer believes your O2's are warm enough when they're not, those positive trims might bleed over to warm closed-loop operation. Make sense?

alchemistz06

Still new to hptuners, but wondering if the PE is causing the issues with those Fuel Cells.

WS6FirebirdTA00

iTrader: (33)

exactly! on start up the trims go too far + for me. i dont know what to adjust though really to delay that on start up. warm starts is where it kills it the most, idle trims go to +10, but hot idle they are 0. sometimes i get this, sometimes i wont. if i reset the trims its fine. it seems to be mainly on cold starts its really bad, the VE is dialed in pretty well. im thinkin about getting new gm o2s, i have densos and i havent been impressed.

soundengineer

iTrader: (16)

cell 22 is Open Loop Acceleration

and I cant remember what cells it uses to add or subtract from WOT... but if you tune your car so that all trims are slightly negative...then you wont have that trimming problem at WOT..
also try to reset your trims once with the scanner and see fi that helps...
when all else fails get a wideband and check it out that way

WS6FirebirdTA00

iTrader: (33)

all trims are -3 to -5 when the car is hot and o2s are hot. when i reset the trims and they have no learn time in FTC 20-22 (it seems it takes a few starts to learn values for these cells) the car runs fine with no + trims at WOT. i checked everything with a WB and WOT is set to 13.1-13.4 across the board, no knock what so ever. part throttle showed to be on as well (besides a few rich decel cells). if i keep resetting trims the problem is non existant but if i dont and keep having all these cold and warm starts, i get shitty and inconsistent values. im gonna drive around for the week without a reset and check at the track and see what comes up.

WS6FirebirdTA00

iTrader: (33)

wait a minute, FTC 22 is open loop accel. so that means the olfa table needs to be decreased since it takes the richer values. PE is set to 13.4 up to 13.1, but olfa is set to 13.0. should i set olfa table to about 13.5?

SSpdDmon

iTrader: (10)

Think about what your saying. Open loop is just that - it ignores O2 feedback, which means no trimming.

I still believe this is related to your O2 sensor being cold. In EFI Live, we can delay this under Engine>Fuel>Trim>Parameters using "Closed Loop Cold Engine Timer" and "Closed Loop Normal Temp Timer." The factory sets these parameters at 190 seconds and 12 seconds. My suggestion would be to lengthen these times so that your O2's have some more time than 12 seconds to heat up (especially with your headers). Also, I'd put the LTFT boundaries back to stock now that your tune is dialed in. I'm 99% certain this should fix your troubles.

WS6FirebirdTA00

iTrader: (33)

ok thanks man. i dont think hp tuners has that table, but i may be wrong.

WS6FirebirdTA00

iTrader: (33)

the stock 2000 trim bound. are odd, like 2500,6502,6503, should i go with them? what is yours at?

SmokingWS6

iTrader: (1)

Make sure all LTFT's are at or below 0, especially under moderate to heavy closed loop accleration. Most write-ups say to achive + or - 5 ltft. I aimed for 0 to -4.

Best way to dail in trims is to log in SD every time you run errands, to and from work if you have the time ect. Then log again with the maf and using one of the many methods, correct for the percentage the maf is throwing off the trims.

SSpdDmon

iTrader: (10)

I kept mine stock (2500, 6502, 6503) because there's a good chance there are other parts of the PCM that expect to see them this way. Besides, if your tune is dialed in throughout closed-loop operation, it shouldn't matter where the boundaries are. So why change them?

WS6FirebirdTA00

iTrader: (33)

i keep my trims -3 to -5 to help prevent them from staying +, like SSpdDmon said, i think its got a lot to do with the cold o2s on start up. ill set them back to the stock settings, it makes sense and now that the ve is dialed in you are right it should be fine, thanks