Lance is falling behind... Updated FATS and VAG results w/ boost & TC blocks ready for analysis
04-21-2005, 10:44 AM
#1
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Lance is falling behind... Updated FATS and VAG results w/ boost & TC blocks ready for analysis
<center><img src="http://pictureposter.audiworld.com/35657/vag.jpg"></center><p>This FATS run was 6.12 ON 100 OCTANE, previous FATS was 6.94 on 92 craptane.
Cat codes came on again yesterday about an hour after clearing them.
Thanks again for your help guys!
Weight 3780, 55 degrees F, 100 oct, MTM A-box chip, RS4 IC's, tire radius 12.7 (235-40-18)
Link to yesterday's FATS and VAG codes:<ul><li><a href="https://forums.audiworld.com/s4/msgs/1973301.phtml">https://forums.audiworld.com/s4/msgs/1973301.phtml</a</li></ul>
Cat codes came on again yesterday about an hour after clearing them.
Thanks again for your help guys!
Weight 3780, 55 degrees F, 100 oct, MTM A-box chip, RS4 IC's, tire radius 12.7 (235-40-18)
Link to yesterday's FATS and VAG codes:<ul><li><a href="https://forums.audiworld.com/s4/msgs/1973301.phtml">https://forums.audiworld.com/s4/msgs/1973301.phtml</a</li></ul>
04-21-2005, 11:22 AM
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Did the lean codes come back as well? 100 octane "alleviated" the problem somewhat, but
something is still note quite right - now your timing (and FATS time) is up to about what it should be for pump fuel, but it is still knock correcting on 100 octane and it shouldn't be at all (with MTM's conservative timing). If you were running lean for some reason, that would be a possible reason for this premature knock, which is why I wondered if the lean codes came back. You might also want to log block 002 to make sure your injector times are where they should be (getting enough fuel).
04-21-2005, 12:45 PM
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Lean codes have not returned since the new MAF. Here is the ign. timing from bad MAF run
I can re-log with the new MAF if it'll help.
Do you suspect O2 sensors or intake leak?
TIME RPM MAF THROT IGNITION TIMING
27.23 4200 106.64 10.88 15.8
27.86 4400 109.89 10.88 17.3
28.48 4560 114.31 10.54 16.5
29.14 4760 118.08 10.54 17.3
29.79 4920 120.56 10.2 21.8
30.46 5080 124.28 10.2 21.8
31.14 5240 126.86 10.2 19.5
31.83 5440 128.92 9.86 21.8
32.53 5600 128.33 9.86 21
33.24 5720 129.92 10.2 21
33.96 5880 131.39 9.52 21
34.69 6040 131.31 9.52 23.3
35.44 6200 132.78 9.18 24
36.18 6320 134.00 9.18 24
36.94 6440 136.17 9.18 25.5
37.69 6600 135.31 9.52 26.3
Do you suspect O2 sensors or intake leak?
TIME RPM MAF THROT IGNITION TIMING
27.23 4200 106.64 10.88 15.8
27.86 4400 109.89 10.88 17.3
28.48 4560 114.31 10.54 16.5
29.14 4760 118.08 10.54 17.3
29.79 4920 120.56 10.2 21.8
30.46 5080 124.28 10.2 21.8
31.14 5240 126.86 10.2 19.5
31.83 5440 128.92 9.86 21.8
32.53 5600 128.33 9.86 21
33.24 5720 129.92 10.2 21
33.96 5880 131.39 9.52 21
34.69 6040 131.31 9.52 23.3
35.44 6200 132.78 9.18 24
36.18 6320 134.00 9.18 24
36.94 6440 136.17 9.18 25.5
37.69 6600 135.31 9.52 26.3
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04-21-2005, 01:09 PM
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Weird, throttle in that log is at 9-10% (cut?) In any case -
the previous lean codes were from the bad MAF, so there's no reason to believe it is running lean now. Your airflow values (MAF g/sec) look reasonable now with the new MAF, so it should be injecting enough fuel (MTM runs plenty rich as well) You could try logging your O2 voltages to be sure.
Other possibilities for the premature knock - heavy carbon deposits? Maybe try running a fuel cleaner through. I have to think it isn't something artificial tripping the knock sensor (like motor vibrations, etc.) because you were able to raise the knock threshold with 100 octane, but it is still lower than it should be.
Other possibilities for the premature knock - heavy carbon deposits? Maybe try running a fuel cleaner through. I have to think it isn't something artificial tripping the knock sensor (like motor vibrations, etc.) because you were able to raise the knock threshold with 100 octane, but it is still lower than it should be.
