lbz34

iTrader: (3)

My ltft are at 25 at idle. stft are about 3 or so at idle. At part throttle cruising I see about 15% or so ltft. At WOT I am seeing 0's all the way across.

What do you ls1 edit guys think.

PS. on the wideband the af's are 14-16 at idle and cruising. WOT is 12.3-12.5's. Seems the computer wants more fuel at idle and part throttle. Except my gas milage is already pretty bad for a cam only car (200 miles/tank).

Thanks
Sean

VINCE

iTrader: (1)

The last time I have seen ltrims like that was when I have a vacuum leak.. I would check all connections again.. Check behind the ls1/ls6 intake to make sure all those little tubes are connected.

lbz34

iTrader: (3)

Car has minor mods I will start with that.
Thanks
Sean

VINCE

iTrader: (1)

No problem. If you list your mods that would help us help you.. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

lbz34

iTrader: (3)

2000 m6 z28.

lid
k&n
ported maf
tsp 228r cam 228/228, 58x.58x. 111 lsa
ls1 edit (new)
Hoosier qtp's/skinnies
weld draglites
hotchkis sfc's
nx wet kit
pro 5.o w/lou handle
tb bypass
tr6 plugs

thats all the mods i can think of.
more comming very soon
just getting a handle on the ls1 edit.

I have experience with other standalone/programable systems (AEM, Hondata, Haltec, etc..) just new to this one.

Help is greatly appreciated.

Sean

jimmyblue

iTrader: (11)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by lbz34:
<strong> 2000 m6 z28.

ported maf

Sean </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Number one suspect....

QuickSilverTA

iTrader: (6)

My car is the same way i have 25%lterm at idle, but at 1/4 gas there lterms are like -2% -1%. From what i've been reading lot of people have this problem. I can't count how many times i've check for vacuum leaks. I know the car isn't running lean, you can tell it's running rich at idle.
https://ls1tech.com/ubb/ultimatebb.p...;f=23;t=004047

eallanboggs

iTrader: (1)

Your on the verge of setting a DTC. You have an air leak on your intake system somewhere.

VINCE

iTrader: (1)

Leak for sure..

Doc99SSx

A vacuum leak certainly is a possibility. Also, the ported MAF will result in high LTFTs. It is usual to run 20 to 25% at idle for LTFT and for the LTFT value to reduce as you go up thru the load cells toward WOT. But I find it very unusual for the LFTF to be 0% at WOT if you were 25% at idle.

In your case, after you have determined that there is no vacuum or you fix the vacuum leak & high LTFTs still persist, I would re-calibrate the flow thru your MAF by altering the MAF table. You do this by letting the LTFT value determine how much to increase the flow value. It is NOT a one time multiplication. In your case, you will be multipling the lower frequency cells by a high number (like 115.0%) and leave the upper cells un-changed. You will have to blend the lower and upper portion of the MAF table together in a smooth curve.

lbz34

iTrader: (3)

Will check tuesday for leaks. Seems I have a vacuum leak. Wideband shows 15 or so at idle and 14-16 at cruise, which is lean in my book. NX MAf kit will replace the ported maf ends as soon as it comes in.

Will kep youg ugys updated.

Thanks for the help
Sean

2K T/A Driver

My car is acting similar to this.. I have a descreened maf though and this is most likely causing the problem from what I have read.. However, it could be a vacuum leak.. How did you go about checking for vacuum leaks?

slick98ta

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by eallanboggs:
<strong> Your on the verge of setting a DTC. You have an air leak on your intake system somewhere. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Another guy here with the same problem...
I actually do pull SES codes.They are for lean fuel bank 1 and lean fuel bank 2.
I've checked for vacum leaks so many times,that i forgot how many.The intake has been on and off like 4 times.My car is actually rich also,and on the windband i'm rich.Its just at idle.

I do still believe its some kind of vacum leak somewhere,but i'm yet to find it.
My mods are:
LS6 intake
cam
MAC headers
ported TB
Lid

98TAauto

iTrader: (2)

my LTRIMS went to +22 after i put my cam in... I suspected the ported MAF and when i took that off and put the stock unit back on the LTRIMS went to -5 <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

I now have the SLP 85mm and my LTRIMS were around +4 with that... I threw on a ported TB and now they are at -6 to -1.6 <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

anything you do to the intake effects the LTRIMS alot

lbz34

iTrader: (3)

I am thinking the same thing. All the car has is a cam tsp228r, ported maf, and lid. Expecting the NX maf kit when it gets here and then I will know if teh ported ends are a big player in my ltft's. I expect the are. Seems my camaro likes to run pretty lean at part throttle and idle. Under WOT it sems to run a bit rich.

BTW- I can find no vacuum leaks. Checked with smoker, and with brake cleaner.

Sean

<small>[ February 28, 2003, 09:22 PM: Message edited by: lbz34 ]</small>