BADSZ28

iTrader: (39)

Ok, I have tried adjusting MAF, timing, transients and nothing has changed the condition. First I thought it was false KR, then too much timing. Well I have a WB now and it goes dead lean when I open the throttle off idle. I am at a loss on this. Please help. The car is dyno tuned by a pro. I asked my tuner and he siad it was the nature of the cam. I think that is BS. I have never heard of this before. It is getting old fast. Car about dies when I leave from a light. Almost got T-boned this morning as it almost died turning left crossing traffic.

jetblast

check your fuel filter, as matter of fact,just put in a new one, i have been tracking your problem, and i would definetly make sure your fuel supply is working properly, now that you have a w/b have you monitored a/r at cruise and wot? you have to have eng. parameter info to successfully diagnose your problem, you need to know 02 sensor activity, fwd. and rear, fuel pressure, maf hz vaulues when the problem occures, visual ck. of any potential intake leaks and exhaust leaks, visually ck. your plugs, #7,8 cyl. always run leaner than the rest, i would ck all of them. how are your fuel trims at idle? did you add larger inj. to the mix. if you have tuning software you should be able to get an idea of whats wrong! good luck

BADSZ28

iTrader: (39)

Well seams my fuel trims at idle are trying to add fuel. 14-16. WB reads OK though. I have no cats so just front O2s and they jump all around so no idea what is going on there. I don't think there is a PID for fuel pressure. I do not have this problem any other time other than transitioning from closed throttle to open. I do have 42lb injectors but the car has been tuned for them by a pro. And the pump is a Racetronix in tank too so no worries there either.

jetblast

what's the injector flow rate vaulues now? you can get a fuel sending unit by auto-meter and comes with the guauge , and if you went to 42lbs. chances are you probalbly need a better pump anyway. if you are not going lean, say when you go from 10% throttle to 30% at cruise doing 80mph, then i say it's a maf table adjustment between 2500hz and mybe 3200-3500hz, did you encrease values in this area of the table?

Frost

iTrader: (45)

are your trims +14 to +16 or -14 to -16?

BADSZ28

iTrader: (39)

Jet Blast: Have a Racetronix pump already stated that. And yes I did change those values in the MAF with no change.

Frost: +16. So I have made some changes to the VE in those cells and will see how she does on the way home today from work.

Quick question, in the histograms on the average setting it reads 0 but on last it shows me on my idea of average that I clearly need to add %. Why is this? What can I do to change this? That can not be correct.

jetblast

ok! if you are confident that your fuel filter is not clogged, and all the pertinent tables are clibrated to match your current cam, than you have to step back and realize it's either air getting in where it's not sopposed to or you are not getting enough fuel, that being said i would take out the fuel injectors and flow them, wait you already did that right?

BADSZ28

iTrader: (39)

The fuel filter is original and the car has 33k on it. May be time, but I am doubting it is the problem. However, I do appreciate the tips of looking from every direction and will consider this. After looking at my LTFTs, I am starting to think my VE is not as dialed in as I payed it to be. I don't know too many people who flow check injectors. Maybe guys who build race motors, but my car is just a street car. If some are off a few % not a big deal and deffinately not the cause of my problem.

Frost

iTrader: (45)

post your tune

jetblast

if you have injector pulsewidth readout, i would monitor them and check for a rise in that transition that you are having problems with , you should not see a drop. i decreased my ve table by 1% columns 400rpm,800rpm from 4.4map-inHg to 14.8map-inHg . my inj. flow rate is set at 65% encrease above stock values[28lbs] and the maf is at 2% above stock, i do not think the idle tables would affect throttle response unless it's idling ruff, you could also try encreasing the idle as to 1000 just to see if throttle response improves, that would put you in a bit higher section of the maps. good luck man!!!

BADSZ28

iTrader: (39)

Thanks jetblast.
My LTFTs keep asking to add 12%+ in the trouble area even though I have added 10% or more. I will try and post my latest tune and log.

jetblast

are you running that trex cam? if so that may be part of the problem, the lsa and duration and lift may not be compensated for just using the tuning tables, a cam like that would want more timing advance and fuel to idle ok and then it may me necessary to enlarge the hole on the throttle plate. if you have binary controls available from your software program, i would take manual control of the afr and set it at 12.5 and the timing on your base spark table in gear and also park/neutral should be advanced from the stock values columns 0 to 1200rpm .08 to .20g gms/cyl at least 4 more degrees from stock that cam may need couple of more degs. and the .24gm/cyl i'm 2deg less adv. then the previous colums. 1600 to 2400rpm advance it 4or6* but only in the .08/.12gm/cyl columns and .16gm/cyl colum 3.5* and the last 2800rpm column 3.5* from .08-.16gm/cyls. look closely at the stock pattern, adding to it, that is all you are doing. you mght want to go over to efiliveforums for more help and research. this settings give me great idle and throttle response, the surrounding columns i kept stock. good luck.