first log, please help.

well guys, i recently installed my AFC along with 510cc fuel injectors, and now since is nice out here( 45 degrees) i decided to start tuning, i got an obd2 cable off ebay and it works good for the price.

Now on to the tuning part, i have my corrections at -12% across the board(hi and low), i logged a litle today and i just wanted to post here to see if i can get some input. this was done with the car not moving. i'll do a pull tomorrow.


Time Trouble codes Fuel status Engine Load (%) Coolant Temp (° C) Short term fuel trim (%) Long term fuel trim (%) Engine RPM Vehicle speed (km/h) Ignition Timing ° Air intake temp (°C) MAF air flow (gram/sec) Trottle (%) Oxy sensor B1-S1 (V) Oxy sensor B1-S2 (V)
6:10:07 PM Closed loop 19.22 41 0.02 0.05 944 0 9 6 2.35 0.48 0.52
6:10:07 PM Closed loop 19.22 49 0.01 0.05 860 0 9 6 4 2.35 0.5 0.46
6:10:11 PM Closed loop 20 49 0.02 0.05 916 0 9 6 4 2.75 0.4 0.46
6:10:14 PM Closed loop 19.61 50 0.02 0.05 932 0 9 6 4 2.75 0.58 0.5
6:10:18 PM Closed loop 19.61 50 0.02 0.05 920 0 9 6 4 2.75 0.52 0.62
6:10:21 PM Closed loop 20 51 0.01 0.05 1,040 0 13 6 5 3.53 0.58 0.6
6:10:25 PM Closed loop 18.82 51 -0.03 0.05 1,248 0 17 6 6 5.1 0.6 0.58
6:10:28 PM Closed loop 18.04 51 -0.03 0.05 1,292 0 17 6 6 5.1 0.48 0.52
6:10:32 PM Closed loop 17.65 52 -0.05 0.05 1,344 0 17 6 6 5.1 0.48 0.38
6:10:35 PM Closed loop 17.65 53 -0.05 0.05 1,372 0 17 6 6 5.49 0.44 0.5
6:10:39 PM Closed loop 17.25 53 -0.03 0.05 1,580 0 21 6 7 5.88 0.48 0.32
6:10:42 PM Closed loop 16.47 54 -0.03 0.05 1,616 0 21 6 7 6.27 0.6 0.62
6:10:46 PM Closed loop 16.47 54 -0.04 0.05 1,740 0 22 6 8 6.67 0.6 0.62
6:10:49 PM Closed loop 16.86 55 -0.05 0.05 1,824 0 22 6 8 7.06 0.62 0.64
6:10:53 PM Closed loop 16.47 55 -0.04 0.05 1,832 0 22 6 8 7.06 0.6 0.62
6:10:56 PM Closed loop 16.47 56 -0.05 0.05 1,864 0 23 6 8 7.06 0.54 0.54
6:11:00 PM Closed loop 16.08 57 -0.05 0.05 1,904 0 23 6 8 7.06 0.6 0.68
6:11:03 PM Closed loop 16.08 57 -0.05 0.05 1,916 0 23 6 8 7.06 0.54 0.54
6:11:07 PM Closed loop 16.08 57 -0.05 0.05 1,988 0 23 6 8 7.84 0.48 0.44
6:11:11 PM Closed loop 15.69 58 -0.04 0.05 2,036 0 24 6 8 7.84 0.52 0.52
6:11:14 PM Closed loop 15.29 59 -0.06 0.05 2,056 0 24 6 8 7.84 0.46 0.46
6:11:18 PM Closed loop 15.69 60 -0.05 0.05 2,128 0 26 6 9 8.24 0.54 0.64
6:11:21 PM Closed loop 15.29 60 -0.05 0.05 2,272 0 27 6 9 8.63 0.6 0.72
6:11:25 PM Closed loop 15.29 60 -0.05 0.05 2,356 0 27 6 9 8.63 0.6 0.56
6:11:28 PM Closed loop 15.29 61 -0.08 0.05 2,396 0 28 6 10 8.63 0.56 0.58
6:11:32 PM Closed loop 15.29 61 -0.07 0.05 2,420 0 28 6 10 9.02 0.54 0.72
6:11:35 PM Closed loop 15.29 62 -0.06 0.05 2,448 0 28 6 10 9.02 0.44 0.44
6:11:39 PM Closed loop 14.9 63 -0.04 0.05 2,468 0 29 6 10 9.02 0.52 0.54
6:11:42 PM Closed loop 14.9 63 -0.07 0.05 2,484 0 29 6 10 9.02 0.58 0.76
6:11:46 PM Closed loop 14.51 63 -0.06 0.05 2,508 0 29 6 9 9.02 0.52 0.56
6:11:49 PM Closed loop 14.51 64 -0.06 0.05 2,524 0 29 6 10 9.02 0.42 0.62
6:11:53 PM Closed loop 14.51 64 -0.06 0.05 2,528 0 29 6 10 9.02 0.52 0.78
6:11:56 PM Closed loop 14.12 65 -0.06 0.05 2,436 0 29 6 8 7.06 0.46 0.48
6:12:00 PM Closed loop 12.94 66 -0.05 0.05 1,468 0 10 6 3 2.35 0.16 0.06
6:12:03 PM Closed loop 19.22 66 -0.04 0.05 796 0 8 6 3 2.35 0.08 0.06


edit: If you guys cant understand this. here is the link to download it, it's an exel file..
http://www.yousendit.com/transfer.php?action=download&ufid=B333A8C715D52AC5

I'm a little concerned with your FT's. I have never seen a logger output FT's as anything less than whole numbers. What logger program are you using? It also seems as though everything is in metric units. I have no problem with that, but it's just a pain to convert. Is it possible for you to convert that to standard?

Anyway, you really need to let the car warm up completely before setting your FT's. You coolant temp reached a maximum of 150 degrees during that log. What you want to do is set your FT's first, then deal with the Hi throttle table later.

But, before we get into this too far, have you done the basics? Spark plugs, leak check, fuel filter, plug wires, etc?

Set the logger up to display STFT, LTFT and rpm. Rev the car to your first Ne Point, hold it there and check the trims. Your goal is to get them to add up to zero. Adjust the SAFC to compensate for a rich or lean condition. If the FT's are positive, adjust the SAFC in the positive direction. Small adjustments are all that is needed. Do this until they add up to zero, then move on to the next Ne Point. Continue this process, until you reach the 4k Ne Point. Take the value from the 4k point and transfer that across the rest of the Lo Throttle map.

For example, if your 4k point ends up being -10%, then every point after that (5k, 6k, etc) should be -10%.

After you set the trims, we can work on the WOT tuning. Just stay out of the throttle, until we get it tuned on the Hi Throttle map. We don't want to melt anything.

I'm a little concerned with your FT's. I have never seen a logger output FT's as anything less than whole numbers. What logger program are you using? It also seems as though everything is in metric units. I have no problem with that, but it's just a pain to convert. Is it possible for you to convert that to standard?

Anyway, you really need to let the car warm up completely before setting your FT's. You coolant temp reached a maximum of 150 degrees during that log. What you want to do is set your FT's first, then deal with the Hi throttle table later.

But, before we get into this too far, have you done the basics? Spark plugs, leak check, fuel filter, plug wires, etc?

Set the logger up to display STFT, LTFT and rpm. Rev the car to your first Ne Point, hold it there and check the trims. Your goal is to get them to add up to zero. Adjust the SAFC to compensate for a rich or lean condition. If the FT's are positive, adjust the SAFC in the positive direction. Small adjustments are all that is needed. Do this until they add up to zero, then move on to the next Ne Point. Continue this process, until you reach the 4k Ne Point. Take the value from the 4k point and transfer that across the rest of the Lo Throttle map.

For example, if your 4k point ends up being -10%, then every point after that (5k, 6k, etc) should be -10%.

After you set the trims, we can work on the WOT tuning. Just stay out of the throttle, until we get it tuned on the Hi Throttle map. We don't want to melt anything.



thanks for the info. Im using a program called obdlogger,http://pages.infinit.net/jsenk/obd.htm here is the link. and i cant get too many samples per second.

But i'm gonna go outside right now, and i'll make sure i log in standard, the program has 3 diff modes. So when i'm setting my FT's, i hold the throtle where my NE point is right, not just at 1k,2k,or 3k,?

thanks for the info. Im using a program called obdlogger,http://pages.infinit.net/jsenk/obd.htm here is the link. and i cant get too many samples per second.


I'll look around and see what the deal is with those FT numbers. Maybe you could check out each of the 3 different modes and see if any of them have whole number values for the FT's.


But i'm gonna go outside right now, and i'll make sure i log in standard, the program has 3 diff modes. So when i'm setting my FT's, i hold the throtle where my NE point is right, not just at 1k,2k,or 3k,?

Correct. I was just using those points as examples. I always like to use the "extra" points in the area where the turbo spools. That is the most likely place to knock.

How do you tune WOT

I'll look around and see what the deal is with those FT numbers. Maybe you could check out each of the 3 different modes and see if any of them have whole number values for the FT's.



Correct. I was just using those points as examples. I always like to use the "extra" points in the area where the turbo spools. That is the most likely place to knock.

i tried, US mode, and it's still not giving me full numbers. I read this one tuning guide that can be found on tuners. but i'm still a little confused, when i start setting the fuel trims, do i add the LTFT and the STFT? Because i got the logger show -.8 in the ST and +.8 in the LT at 1k rpm, with the correction at -8.

How do you tune WOT

That's kind of a broad question......can you be a little more specific?

i tried, US mode, and it's still not giving me full numbers. I read this one tuning guide that can be found on tuners. but i'm still a little confused, when i start setting the fuel trims, do i add the LTFT and the STFT? Because i got the logger show -.8 in the ST and +.8 in the LT at 1k rpm, with the correction at -8.

Ok, well let's just roll with the 0.x numbers.

You are correct, add them together and if they are close to being zero, that Ne point is set. STFT is Short Term Fuel Trim and LTFT is Long Term Fuel Trim. The STFT is a reflection of what's happening right now and the LTFT is more of a running average. As the ECU "sees" a rich or lean condition, it compensates using the STFT. As the condition persists, the ECU transfers the STFT value to the LTFT and drops the STFT to zero.

Basically, if you sat there long enough, maybe about 5 minutes. You would see the ST & LTFT reach zero in your example. Did that make sense??

Just do the same thing to your other Ne Points and post back when you finish with the 4k Ne Point.

That's kind of a broad question......can you be a little more specific?

Well, My question is kinda under full boost At higher rpm when my foot is mashed and my A/f RATIO keeps on changing (only slightly but enough so I can't tell at what rpm I need to subtract fuel, (AT WOT I'm running down in low 10/1 or lower (just did it that way to be safe until I knew for sure I could get it right)

Open-loop fuel tuning is complicated. I don't see any engine mangment devices in your signiture. What do you use?

So what you mean, is that you have no way to log the correlation between your WBO2 reading and rpms?