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vsocks1
June 28th, 2009, 05:55 AM
Just finished a head/cam/intake project on my LS-6 2003 Z06. Start and runs really well at this point. No apparent leaks or anything mechanically suspicious. In logging I see that the passenger side is consistantly running about 10% higher LTFT than bank 1. For example if bank 1 is at 1% bank 2 will likely be 11%.
Where do I start to troubleshoot? Don't see or hear a air leak or whistle. O2 sensor seems to be switching voltages properly - just has a lowerverage than bank 1 thus adding fuel. Bank 1 average was right at .450 and bank 2 was closer to .380 or so.

Please give me some ideas or places to test. Thanks!

mr.prick
June 28th, 2009, 06:47 AM
NBO2 maybe dead.
Is O2 switch point {B4105} 450.00?

vsocks1
June 28th, 2009, 08:20 AM
NBO2 maybe dead.
Is O2 switch point {B4105} 450.00?

The O2 switch point is the same for bank 1 & bank 2.
It is currently set like below:

CL Mode Bank 1 Bank 2

0 450.012377 450.012377
8 450.012377 450.012377
16 389.992642 389.992642
24 440.009088 440.009088
32 499.994914 499.994914
40 524.986182 524.986182
48 524.986182 524.986182
56 524.986182 524.986182
64 544.992761 544.992761

mr.prick
June 28th, 2009, 09:46 AM
Try setting {B4105} to 450.00 across the board,
the older LS1 OS' have mixed values but if you look at the newer
OS' this table is 450.00.

If you want to track {B4105} you need a calc.pid and log it's supporting PIDs
{****.****} = one of the following PIDs GM.DYNCYLAIR_DMA,GM.CYLAIR_DMA,GM.DYNCYLAIR,CALC.C YLAIR


#Units Low High Fmt Expression
#------------ ------------- ------------- --------
*CLC-00-018
None 0 64 0.0 "lookup({****.****}, 0,0, 4,4, 8,12, 12,30, 16,36, 20,40,24,44, 28,50, 32,54, 36,54, 40,54, 44,54, 48,54, 52,54, 56,56, 60,64, 64,64, 68,64, 72,64, 76,64, 80,64, 84,64, 88,64, 92,64, 96,64, 100,64, 104,64, 108,64, 112,64,116,64,120,64,124,64, 128,64, 132,64, 136,64, 140,64, 144,64, 148,64, 152,64, 156,64, 160,64, 164,64, 168,64, 172,64, 176,64, 180,64, 184,64, 188,64, 192,64, 196,64, 200,64, 204,64, 208,64, 212,64, 216,64, 220,64, 224,64, 228,64, 232,64, 236,64, 240,64, 244,64, 248,64, 252,64, 256,64, 260,64, 264,64, 268,64, 272,64, 276,64, 280,64, 284,64, 288,64, 292,64, 296,64, 300,64, 304,64, 308,64, 312,64, 316,64, 320,64)"
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ----------------
CALC.CLMODE F018 CLC-00-018 None Air "Closed Loop Mode"

vsocks1
June 28th, 2009, 10:20 AM
Set them all to .450 and took it for a spin. The LTFT's were lower than before but still almost a 10% difference between banks.

mr.prick
June 28th, 2009, 12:22 PM
You are resetting LTFTs after a re-flash, right?
An exhaust leak could cause problems, try swapping B1 and B2 sensors to see if the inconsistency follows the sensor.
FWIW my Fbody has about 3% difference between banks.

vsocks1
June 28th, 2009, 09:27 PM
No exhaust leak that I can see. The STFT's log the same as the LTFT's - if the drivers side is +2% the passenger side is +12%.

joecar
June 29th, 2009, 02:49 AM
Post some logs showing HO2S11 and HO2S21.

vsocks1
June 29th, 2009, 08:48 AM
Here is the log file & tune!

vsocks1
June 30th, 2009, 02:04 PM
Any feedback after posting the logs? I am thinking I have a lazy O2 sensor....

joecar
July 1st, 2009, 02:11 AM
Maybe you do have a bad O2 sensor... swap them left/right and see if the trims follow the sensors.

You will need to correct your MAF and VE tables.

I would set the switchpoints back to stock.