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Rusty
November 19th, 2009, 08:11 PM
I am still trying to get a LS6 to idle. I have confirmed injector flow rate is correct by model number. I have tried 50+ flashes and I am starting to get expected results based on cal changes. I have a large cam which gives real high MAP while the engine idles between 800 and 1200 RPM. I have found that the stock corvette LS6 VE tables are not even close when MAP above 70KPa and below 1400 RPM. I have autoVE and tried autoMAF. The autoVE wants me to raise VE for the lean conditions, but the airflow from fudged VE table (MAF disabled) is more than twice what is typical.

I believe that my problem is related to desired airflow, so I used RAFIG after reading many EFI Live treads. After applying the small changes to desired airflow from RAFIG, I really did not see an improvement.

I am attaching a log file (only 24 channels) with dual wide band data and typical RAFIG PIDS. The car was started cold and the MAF was connected. I tolerated the 20+ AFR so I can so you my results. Keep in mind that the wide bands will jump down to 9.6 AFR when AFR goes above 22 AFR.
All opinions are welcomed!

CAM SPECS:
lift .647 intake and exhaust
250 duration @ .050

Using:0911 PCM (OS 12220588)

Please help.....

rally1
November 19th, 2009, 09:48 PM
You could start buy putting it into open loop as your short term fuel trims are maxing out at +50 and that wont be helping with a stable idle, your getting knock at idle which is very strange as the timing is not overly high, can you post your tune?

mr.prick
November 20th, 2009, 03:29 AM
Bank2 is off quite a bit from bank1,
I would start by checking for an exhaust leak and/or the calibration of the sensors.

Get AFR in line before using RAFIG, lean AFR will give bad RAFIG values.
You should not be that lean at cold start with commanded AFR so low.