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Old 11-23-2005, 03:07 AM
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Question running lean

whats wrong? i have a 98 z28 a4 it has a 02 ws6 engine in it. i just got the car from a friend and it never had any codes. now it is showing a ses code it says that bank 1 is running lean then i cleared the code at autozone.next day it came on again and it said bank 1 and bank 2 my friend at autozone said it was most likely the mas air but i can figure it out i have a ls6 intake,lid,ported tb,3 inch randome tech exaust and the usual free mods
any help????????????????

it would help thanks. shaun
Old 11-23-2005, 03:38 AM
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It means your LTFTs are beyond the threshold, +25 I think. I got mine back in line by adjusting the IFR table. A leak could cause this too, so I'd check for that first (exhaust or intake leak most likely).
Old 11-23-2005, 12:16 PM
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Question

thanks for the help predator. well im not that good with the tech talk lol but i do know about cars.what does ltft' s mean?. my car does have a sucking sound but i thought it was the lid then i left it started and gave it throttle wile i was under the hood and it sounds like its coming from the top or from the belt. do i need a bigger mas air like the slp?
once again thank you. shaun
Old 11-23-2005, 12:22 PM
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Chances are it's something like an exhaust leak. It could be the MAF if some of the tiny wires inside were damaged. The easy way to check that is to find someone with a MAF you could borrow, swap 'em and see if you get the same problem. Either way, the code you're getting is most likely generated from the sensor in the exhaust detecting too much oxygen, which means either you PCM is not supplying enough fuel or the exhaust isn't sealed and is letting outside air in.
Old 11-23-2005, 01:11 PM
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Long Term Fuel Trims. The lean code means that your LTFTs are greater than the threshold (+25 on my 2000 Trans Am). You have too much air relative to fuel and the pcm is beyond its scope to bring them back in line. You need to find out why you have too much air. The stock MAF is fine if it's working correctly. As SSpd said, try swapping out your MAF and see if you have the same problem, and that will eliminate the MAF from the equation. Then check for leaks, in exhaust or intake. If you didn't have those lean codes before, and you haven't modded the car since but have codes now, it seems logical that you have a leak. Go thru your exhaust, headers, intake and tighten everything up.




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