Help!.. LTFTs out of control!!

Ok, here goes...

99 Cam z-28 a4, slp longtubes, slp cats, slp loudmouth, granatelli lid, stock maf w/ported housing, tb bypass, k&n, everything else is stock..

ok, when i purchased my car, it had hypertech on it, i "deprogrammed" my car, however i think it leaves stuff in there.. who knows. anyway, I dont know if i have a real "stock" bin so if anyone has a 99 ss or z-28 lemme know.. i need your maps. However, when i log my LTFTs they are between +9 and +21.. they jump all over the place.. if i average them its like +17 or +18.. all over the map. Anyone have any clue what could be causing this?? Is it my o2s, vacuum leak, who knows??? i can send anyone a log file so you can see if you dont understand what i am trying to say. I dont know if its just the old tuning or a physical problem w/ my motor.. plz help. I cant tune unless i figure it out.... :banghead:

If you have another unmolested (stock) mass air housing, use it-and check your fuel trims again.

I can email you a copy of my stock (99) bin file if you like.

ok will do.

Please send me your bin. my email is [email protected]

Thanks.

LTFTs should be consistent vs FTC (fuel trim cell).
The LTFT is likely (almost certain) to be different
in different regions (RPM, MAP) of operation. It
usually tends to be richer at idle and leaner as
you go up (my trims are like -10 at idle and -1
at upper MAP, RPM).

LT headers' effect on O2s is a problem for these
cars, you may see the LTFTs drift around all the
time as the O2s heat up, cool down, mess the
mixture sensing around. No generally-accepted
solution for that, that I've seen. Though header
wrap might help you keep them hotter and more
satisfied, have seen no before / after reports of
anyone who's taken me up on that suggestion.

And do inspect the MAF for buggery... preinstalled
Hype-Tech is one of the seven warning signs the
previous owner was a dumb-ass ;)

Quote:

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Originally Posted by jimmyblue

(my trims are like -10 at idle and -1 at upper MAP, RPM).

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So it's rather normal to see much lower numbers in the upper left portion of the ltft histogram window while the rest of the chart is right in line?