Take a look at my datalog?
 

I'm seeing some hesitations and I'm a bit worried.

What do you think?

Datalog here:
http://forums.nasioc.com/forums/show....php?t=1188766


Thanks
Rob

Where/when exactly do you get hesitation?

There is a small timing jump at 2400-2500rpm (but no knock), but I don't think you'd feel it. The low KC of 4 at 3390 indicates it's pulling timing there and you may feel that as a hesitation. You are knocking there and prolly in the 6000-6500rpm range too. Bad tank of gas maybe? Or something else...

Those AFRs must be from the stock sensor, right? They seem to peg at 11.02. Some readings from a wideband might tell us more.

On another note... I think you'd spool a little quicker if the lower boost levels were leaned out a little. 11:1 AFR at only 9-10psi is a little conservative IMO.

Mostly seeing hesitations in the midrange, sorry. It's not just noticeable to me, I had my friend in the car the other day and he immediately remarked on how it pulls for a sec then slows and pulls again.

I'm pretty sure it isn't a bad tank of gas, as I recall having this problem on the last tank, too. I use Shell 91. I have to fill up again in the next day or so, we'll see. Could be winter gas having a hard time keeping up with the tune?

Ed tuned it in late August, I believe.



BTW, what should my KC values look like?

I am not an expert on the stock ECU's knock correction, so keep that in mind. I've fooled with UTEC for a couple years, but I've messed around with the OpenECU stuff lately too. Anyway...

If the timing map was perfect for the current conditions then they would be 0, but because you have positive values the ECU is actually adding timing. That's fine and may be because of nice cool weather. It's just the ECU adjusting. Generally you see positive numbers on a tuned car

I notice that they jump at the two places I mentioned, particularly at 3390 where the timing jumps down a couple degrees briefly. It's not much, but that would be my first place to look for a hesitation, but the culprit may also be in the fuel somewhere (maybe there).

It would be nice to get some real AFR numbers in the log with a wideband.

If a fresh tank of gas doesn't help (and it prolly won't) try cleaning the MAF with some CRC MAF cleaner (still doubtful) and maybe check around for air leaks after the MAF (they would be minor if any). Is the air filter plugged? CELs lately?

What mods do you have on the intake side? Have you changed anything since the tune in Aug?

Thanks.

No changes since the tune. Intake mods include cobb short ram, turbo inlet, big tmic/hoses.

No cels, air filter good. The maf was sparkling last I checked just before the tune, I'll look at it again.

I asked Ed to look at it, but he doesn't often respond, hopefully he checks his email and pms.

Keep in mind that the actual MAF sensor wire is up inside the MAF housing out of sight, so spray up in there and let it drain out. The obvious little bulb is the IAT sensor. You may already know this, and I doubt it's a dirty MAF anyway.

I was asked this in the original thread. How do I check that?

If you can check it, you prolly can change it. OpenECU stuff or StreetTuner maybe. Ed could tell you (as I assume he keeps copies).

What are you logging with?

ecu explorer

Go to openecu.org and find the freeware for copying an image of your ECU and then open it up offline with the other freeware. Sorry, I'm having a mindblock on the freeware names right now. I have it and have done it.

Wait, what did Ed tune using?

Protuner.

I think Ecutek locks you out of your ECU, but I don't know if ProTuner does too - I don't think so.