HumpinSS

iTrader: (1)

and falling on its nose. Ok I have been trying to diagnose this problem for months on end now and I am my last wits with it.

Problem
The car pulls nice and strong until it gets to 5K from 5k to 5.5k the car feels as though it is breaking up. It falls on it face and knda struggles to pull this 500 rpm. After around 5.5k it seems to straighten out and continue to pull again to about 6k which is were i shift. At first i thought it may have been a plug and wire issue, so i bought NGK iridium TR55 and a set of MSD wires and changed those yesterday and to my dismay it is still doing it. The plug change helped a little but didnt get rid of the problem. I have EFI live and when on my lunch break I am gonna do some blasts and get some data but I need someone to help me diagnose the problem while looking at the data recorded.



What parameters would i need to log in order to get the most pertinent information about whats going on

1999_SS_M6

monitor your KR (knock retard) data. Disregard if you've already done this, but given the description that you gave, and the fact that you didn't eliminate KR as something you've already investigated, that's where I'd start. A value of 3 or higher would be a clue you're on the right track. Also, monitor total engine timing in conjunction with the KR, if you're getting significant KR, there will be an associated reduction in ingnition timing, hence the "falling on it's nose."

HumpinSS

iTrader: (1)

ok will do data soon to follow

HumpinSS

iTrader: (1)

<font class="small">Code:</font><hr /><pre>
RPM rpm ADV °BTDC KNOCK deg HO2 B1S1 mV HO2 B2S1 mV LTFT B1 % LTFT B2 % MAF lb/min VSS mph AFR :1
4769 23.5 2.9 868 868 9.38 9.38 23.3 86.4 11.7
4801 23.5 2.81 859 868 9.38 9.38 23.7 87 11.7
4833 24 2.81 864 864 9.38 9.38 23.8 87.6 11.7
4866 24 2.73 864 864 9.38 9.38 23.7 88.2 11.7
4901 24 2.73 859 855 9.38 9.38 24.7 88.9 11.7
4949 22.5 3.96 868 851 9.38 9.38 24.7 89.5 11.7
4977 22.5 3.87 859 851 9.38 9.38 25.3 90.1 11.7
5022 23 3.87 851 851 9.38 9.38 22.8 90.7 11.7
5033 23 3.78 842 868 9.38 9.38 24.5 91.3 11.7
5057 23.5 3.69 864 855 9.38 9.38 25.8 91.3 11.7
5095 23.5 3.61 859 851 9.38 9.38 24.7 92 11.7
5116 23.5 3.61 855 846 9.38 9.38 26.5 92.6 11.7
5139 24 3.52 833 868 9.38 9.38 24.3 93.2 11.7
5171 24 3.43 846 859 9.38 9.38 26.3 93.2 11.7
5185 24 3.34 859 851 9.38 9.38 25.7 93.8 11.7
5214 24 3.34 842 447 9.38 9.38 22.8 94.4 11.7
5183 25 3.25 825 651 9.38 9.38 24.3 94.4 11.7
5279 24 3.96 842 738 9.38 9.38 22.5 95.1 11.7
5262 24.5 3.87 825 603 9.38 9.38 23.3 95.7 11.7
5299 25 3.87 855 851 9.38 9.38 26.7 96.3 11.7
5364 25 3.87 846 859 9.38 9.38 26.1 96.3 11.7
5358 25 3.78 846 855 9.38 9.38 27.1 96.9 11.7
5391 25.5 3.69 851 855 9.38 9.38 27.4 97.6 11.7
5416 25.5 3.61 851 855 9.38 9.38 27.1 98.2 11.7
5454 26 3.61 846 872 9.38 9.38 26.1 98.8 11.7
5501 26 3.52 846 864 9.38 9.38 27 99.4 11.7
5505 26.5 3.43 838 868 9.38 9.38 26.5 100 11.7
5540 26.5 3.34 859 851 9.38 9.38 25.9 100 11.7
5563 27 3.34 846 864 9.38 9.38 27.1 101 11.7
5577 27 3.25 842 864 9.38 9.38 27 101 11.7
5613 27.5 3.25 851 851 9.38 9.38 25.9 101 11.7
5632 26.5 3.17 855 872 9.38 9.38 23.1 102 11.7
5613 34.5 3.17 855 794 11.7 12.5 3.77 100 11.7
</pre><hr />

T/A rocker

!!! the columns are kinda off, but if I'm reading that data correctly, you got serious KR issues, also looks like you are running way lean, if this is WOT data, and that could be the cause.

jimmyblue

iTrader: (11)

Much too lean and knocking all the way. Tell us
which aftermarket / ported MAF you have

HumpinSS

iTrader: (1)

It was a home prot job. Here are some more numbers with the Injector duty cycle logged

<font class="small">Code:</font><hr /><pre>
VSS RPM ADV KNOCK O2 B1S1 O2 B2S1 Duty Cycle Bank 1 Duty Cycle Bank 2 LTFT B1 LTFT B2 ECT IAT AFR
88.9 4901 22.5 3.96 855 877 69.6 69 8.59 7.81 176 95 11.7
88.9 4929 22.5 3.87 864 872 70 69.4 8.59 7.81 176 95 11.7
89.5 4959 22.5 3.87 877 872 70.7 70.1 8.59 7.81 176 95 11.7
90.1 4993 22.5 3.69 864 872 70.9 70.3 8.59 7.81 176 95 11.7
90.7 5020 23 3.61 868 868 71 70.4 8.59 7.81 176 95 11.7
91.3 5044 23 3.61 851 872 71.1 70.4 8.59 7.81 176 95 11.7
92 5074 23 3.52 868 872 71.2 70.5 8.59 7.81 176 95 11.7
92.6 5105 23.5 3.43 864 864 71.9 71.3 8.59 7.81 176 95 11.7
93.2 5139 23.5 3.34 868 864 72.1 71.4 8.59 7.81 176 95 11.7
92.6 5169 24 3.34 859 877 71.5 70.9 8.59 7.81 176 95 11.7
93.2 5162 24.5 3.25 851 855 71.1 70.5 8.59 7.81 176 95 11.7
93.8 5210 24.5 3.25 855 803 69.2 68.6 8.59 7.81 176 95 11.7
93.8 5194 24.5 3.17 816 625 65.8 65.3 8.59 7.81 176 95 11.7
94.4 5225 25 3.17 829 747 67.2 66.6 8.59 7.81 176 95 11.7
95.1 5225 25 3.08 842 668 69.8 69.1 8.59 7.81 176 95 11.7
95.1 5255 25 3.08 803 664 66.2 65.6 8.59 7.81 176 95 11.7
95.7 5309 25 3.17 868 716 70.8 70.1 8.59 7.81 176 95 11.7
96.3 5305 24.5 3.96 829 690 68.9 67.6 8.59 7.81 176 95 11.7
96.9 5352 25 3.96 838 734 70.5 70.2 8.59 7.81 176 95 11.7
96.9 5352 25 3.87 838 664 70.5 70.2 8.59 7.81 176 95 11.7
96.9 5395 25 3.87 846 807 71.7 71.1 8.59 7.81 176 95 11.7
97.6 5396 25.5 3.78 842 829 72.4 71.7 8.59 7.81 176 95 11.7
98.2 5444 25 3.69 855 859 73.4 73.4 8.59 7.81 176 95 11.7
98.8 5475 25.5 3.61 846 872 75.5 74.8 8.59 7.81 176 95 11.7
99.4 5496 25.5 3.61 864 864 76 75.1 8.59 7.81 176 95 11.7
100 5526 26 3.52 851 868 75.8 75.1 8.59 7.81 176 95 11.7
100 5540 26 3.43 864 855 76.4 75.7 8.59 7.81 176 95 11.7
101 5565 26.5 3.34 859 864 76.3 75.6 8.59 7.81 176 95 11.7
101 5592 27 3.34 851 855 75.7 75 8.59 7.81 176 95 11.7
101 5604 27.5 3.25 859 864 75.5 74.8 8.59 7.81 176 95 11.7
102 5638 27.5 3.25 864 864 74.1 73.7 8.59 7.81 176 95 11.7
102 5663 27.5 3.17 851 846 67.1 66.4 8.59 7.81 176 95 11.7
100 5583 34.5 3.08 890 855 38.3 38 11.7 10.9 178 95 11.7
</pre><hr />