This is not a crosspost - my previous logs had insufficient data. In any case, as the story goes, for a while I was wondering why my car would intermittently hesitate from about 2psi vacuum to 4 psi boost while accelerating from a stop. I swapped out my old battery for a new one, imagining that had cleared the problem, but it turns out that Im still feeling a "lean spot" early in the powerband where I think the car is pulling timing.

Car/crap underhood:

MY03 USDM WRX
Ecutek reflash (17psi)/dyno tune
UP + TBE, catless
Samco I/C y-pipe
JDM STi BPV
Optima 35R
Stock intake w/ kn panel
Ground kit

EGT sensor has been replaced with a 2.2kOhm resistor, which pegs EGTs at 1274 degrees F. Running the stock narrowband O2. This log represents a 3rd gear pull from 2500-6000 rpm. Level ground, 73 degrees F, 60% humidity.

RPM MAP A/F A/F Thrt. MAF Intk. Ign. Knock Inj. Wstg. F.Pmp. AFR Knock
(psi) Learn Corr % Tmp. Corr. Duty Duty Duty Signal
2491 3.773 0.00 3.91 3.53 8.29 95.00 43 0 4.25 13.33 33.33 13.67 0
2499 4.933 0.78 -4.69 9.02 13.67 95.00 42 0 5.86 15.29 33.33 12.29 0
2439 12.914 1.56 -3.13 31.76 39.85 95.00 30 0 12.49 23.53 33.33 14.47 0
2516 14.365 1.56 3.91 50.20 39.55 95.00 29 1 15.03 31.76 66.67 13.55 0
2574 15.525 2.34 11.72 60.00 43.35 95.00 29 6 17.02 39.61 66.67 14.01 0
2651 16.686 2.34 0.00 72.55 48.33 95.00 27 7 18.10 50.59 66.67 12.98 0
2724 17.847 2.34 0.00 74.90 53.90 95.00 24 7 20.34 58.82 100.00 14.24 0
2895 21.184 3.91 0.00 75.69 67.35 95.00 18 5 26.55 58.82 100.00 12.17 0
2895 21.184 3.91 0.00 75.69 67.35 95.00 18 5 26.55 58.82 100.00 12.17 0
2996 23.651 4.69 0.00 75.69 79.11 95.00 15 6 32.60 61.18 100.00 11.94 0
3091 25.827 4.69 0.00 75.29 90.62 95.00 13 6 38.91 62.75 100.00 11.48 0
3248 28.729 5.47 0.00 75.69 101.15 95.00 13 6 46.42 65.10 100.00 11.37 0
3356 30.616 5.47 0.00 75.69 110.18 95.00 12 6 53.69 65.49 100.00 11.37 0
3474 31.196 7.81 0.00 75.69 113.27 93.20 12 6 58.54 64.31 100.00 11.25 0
3625 31.051 7.81 0.00 75.69 116.63 93.20 12 5 60.32 63.53 100.00 11.25 0
3750 31.051 7.81 0.00 76.08 123.82 93.20 12 5 66.40 63.53 100.00 11.37 0
3880 30.906 7.81 0.00 81.96 127.97 93.20 11 4 69.53 63.53 100.00 11.25 0
4011 30.906 7.81 0.00 86.67 132.69 93.20 12 4 74.43 63.14 100.00 11.25 0
4144 30.906 7.81 0.00 89.41 135.28 93.20 12 4 76.90 62.75 100.00 11.25 0
4252 30.906 7.81 0.00 95.29 139.70 93.20 13 5 79.81 63.14 100.00 11.25 0
4383 30.906 7.81 0.00 100.00 143.86 93.20 12 5 82.29 64.31 100.00 11.25 0
4529 31.196 7.81 0.00 100.00 151.50 93.20 13 6 85.02 65.49 100.00 11.25 1
4632 31.341 7.81 0.00 100.00 156.28 91.40 13 7 87.95 66.67 100.00 11.25 0
4729 31.196 7.81 0.00 100.00 157.86 91.40 13 7 88.77 67.84 100.00 11.25 0
4892 31.486 7.81 0.00 100.00 164.11 91.40 14 6 89.75 68.63 100.00 11.25 0
5020 31.196 7.81 0.00 100.00 167.76 91.40 14 6 93.17 69.02 100.00 11.25 0
5144 31.051 7.81 0.00 100.00 171.50 91.40 14 4 95.47 69.80 100.00 11.48 0
5219 30.616 7.81 0.00 100.00 174.41 91.40 16 3 95.75 70.98 100.00 11.37 0
5407 30.325 7.81 0.00 100.00 176.07 91.40 17 2 96.89 71.76 100.00 11.25 0
5519 29.890 7.81 0.00 100.00 177.31 91.40 17 3 97.72 72.94 100.00 11.25 0
5576 29.455 7.81 0.00 100.00 181.47 91.40 16 1 98.73 74.12 100.00 11.25 0
5682 29.020 7.81 0.00 100.00 181.89 91.40 16 1 98.18 78.04 100.00 11.25 0
5814 29.020 7.81 0.00 100.00 183.50 91.40 16 0 99.22 79.61 100.00 11.25 0
5878 24.957 7.81 0.00 0.00 183.04 89.60 12 0 0.00 0.00 66.67 11.37 0

Seems like below 4K RPM my af/correction is all over. Then the injectors are nearing 100% duty above 5K. The knock sensor picks up once, but the ECU doesn't pull timing right afterwards. Knock correction also seems to be a scattershot.

Normal or not? Any thoughts? Also, the car still takes a lot of turns to start despite my new battery - sometimes I have to try twice. I was told over the weekend it could be my crank angle sensor going bad.

Your input is greatly appreciated!

Ben

is there a reason you took so long to get to 100% throttle?

im sorry im not much help with this stuff, still learning it. Your ignition timing seems high around the area you are talking about, but that may be just because your not at 100% throttle.

I wanted to roll onto the gas so I could have some logs of what was happening at part throttle since that's where I was originally having issues (~25% throttle +/- 10%). Of course, the disadvantage is that it's yet another variable to account for.

I don't really see any timing being pulled. It cuts down right as boost rises, but it is supposed to do that. Timing doesn't look out of place.

That is odd to see those two 14.xx AFR points at 2600-3000rpm. Can you confirm the behavior with a wideband?

Hard to say much else without being able to see your fuel and timing maps.

I have recently been experiencing the same thing on my 02 with an ecutek tuned to 19lbs.

in between 2500-3500 rpm, 0psi ~ 5psi I get a hesitation at PART throttle and my A/F leans out >15 (based on watching the LM-1 display). If I do this WOT everything looks fine, and in either case I my A/F's settle to about 11.5 like yours once the boost really kicks in.

I am interested to see what people think about this topic.

great! er...sorta. well, its just good to know Im not the only one getting this weirdness.

Keep the ideas flowing...