PO171 &174 System too Lean(Bank 1&2)???
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I have some of the following mod's. Stage IIx heads, 229 cam, LS6 intake, 30# SVO's, BBK TB, SLP MAF, MAF-T, FLP LT's, and Ed Wright PCM. I keep getting these codes but everything seems to be adjusted right as far as AutoTap goes. I also have a warm surge issue to deal with as well.
Any suggestion's would be wonderful. Thanks !
Doug
00 Pontiac
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Doug
00 Pontiac
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I had the same exact problem. At first the codes would cycle on and off,but eventually the SES stayed on. My symptoms were; surging idle, hard starting, backfiring on deceleration at highway speeds, problems with TC operating properly.
The problem was the MAF ends (actually ends from a GMAF with stock electronics).
I'm pretty sure these codes mean you are 25% lean, which is bad.I assume you've tried to richen it up with the MAFT with no results. Try switching to you stock MAF for at least a week and see what happens. Make sure to disconnect your battery doing the swap.
BTW - what are your o2 readings, fuel trims at when the codes are set? Mine would only come on at part throttle, never idle or WOT.
The problem was the MAF ends (actually ends from a GMAF with stock electronics).
I'm pretty sure these codes mean you are 25% lean, which is bad.I assume you've tried to richen it up with the MAFT with no results. Try switching to you stock MAF for at least a week and see what happens. Make sure to disconnect your battery doing the swap.
BTW - what are your o2 readings, fuel trims at when the codes are set? Mine would only come on at part throttle, never idle or WOT.
#3
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I have some of the following mod's. Stage IIx heads, 229 cam, LS6 intake, 30# SVO's, BBK TB, SLP MAF, MAF-T, FLP LT's, and Ed Wright PCM. I keep getting these codes but everything seems to be adjusted right as far as AutoTap goes. I also have a warm surge issue to deal with as well.
Any suggestion's would be wonderful. Thanks !
Doug
00 Pontiac
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Doug
00 Pontiac
To trigger lean codes either atap is lying, anlyzing the data is incorrect or maybe faulty 02s, IAT or ECT sensor and PCM is being told it is that lean.
Do the plugs show a lean condition?
if that lean are you getting lots of knock ?
There should be zero need of a MAFT if the PCM tuner knows what the hell they are doing.
Yank the MAFT and see if it has gone bunko for I have seen this when it goes bad, also MAF could be the problem.
You need a good PCM recording and data analyzed to pinpoint the problem.
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I am having this same problem with my bird.. Have both codes for system to lean and also lean codes for the rear o2 sensors? but not the front... I'm new to the LS1 just got the car last week and then out of no where it started acting funny.. im getting a weird surge at about 2,000 to 2,500 RPM, it starts to act like its falling on its face then takes off like crazy and only does it until its fully warm. then the problem is gone, except for the light, my first thought was maybe the intake was leaking or something but now im not so sure, any help would be awesome.. No mods 92,000 miles
#6
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What's awesome is reviving a thread from 2002. Especially one with a post from JR.
Look for a vacuum leak. Check the PCV hose where it connects to the intake passenger side behind throttle body. That hose is known to rot and leak. Clean MAF. Check fuel pressure on rail. S/B 58 psi.
Look for a vacuum leak. Check the PCV hose where it connects to the intake passenger side behind throttle body. That hose is known to rot and leak. Clean MAF. Check fuel pressure on rail. S/B 58 psi.
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well figured it'd be easier to get some tips from someone that has already had to deal with this issue.. lol and thanks already cleaned the MAF didn't really think about the pcv guess i need to go to the shop today and get my pressure tester and check that also... Also sorry for pulling up an old thread.. I just searched my codes and this is the first one that came up with both bank lean codes..
ok Fuel pressure is good.. PCV is good Can hear a vacuum leak though sounds like its all around the TB and EGR Tube so thats going to be the next things i look at.. I played around with some stuff and the light went out but still hear a leak.. Is it real common for the intake to leak on these engines?
ok Fuel pressure is good.. PCV is good Can hear a vacuum leak though sounds like its all around the TB and EGR Tube so thats going to be the next things i look at.. I played around with some stuff and the light went out but still hear a leak.. Is it real common for the intake to leak on these engines?
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#8
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get rid of the aftermarket slp maf sensor... put the stock one on...
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06MonteSS / DiabLew Tune
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2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com