[Dot584]

So I have read through the HOW TO calibrate MAF and MAF 101 many times as well as the steps in the help file but I am still unclear on a lot of things. Its my first time tunning and I dont want to mess anything up so here is my log, 2nd gear starting at about 1500 RPM and slowly accelerating untill the MAF reads over 100. To me it looks like I did it right except for that in the log provided in the how to, the boost goes up to 12 and mine is negative all the way. (A result of slowly accelerating) Is this how it should be or should I boost at 3000 RPM like in the example log?

 

[dougefresh_]

So I have read through the HOW TO calibrate MAF and MAF 101 many times as well as the steps in the help file but I am still unclear on a lot of things. Its my first time tunning and I dont want to mess anything up so here is my log, 2nd gear starting at about 1500 RPM and slowly accelerating untill the MAF reads over 100. To me it looks like I did it right except for that in the log provided in the how to, the boost goes up to 12 and mine is negative all the way. (A result of slowly accelerating) Is this how it should be or should I boost at 3000 RPM like in the example log?

Don't worry it is confusing as hell when it's your first time doing any tuning. You did it right, but you should redo it, and ONLY log MAF g/s, MAF volts, LTFTs. Leave the display on MAF g/s as I'm sure you did when you took the above log. When you have all those other PIDs selected (app, rpms, etc. etc.) the resolution of the datalog sucks. If you only select those three, you'll have a lot of data points, and you want that for the maf volts, because you want to see exactly where the breakpoints are. I always do 3 maf g/s tests, as there is always some 'overlap'. By overlap, I mean different LTFT's for the same MAF voltage. So, how do you know which one do you use? Do a few maf g/s tests, and it'll give you a better idea of what the 'true' maf voltage breakpoint is. Does that help at all?

 

[bova80]

he should log STFT as well.

 

[dougefresh_]

he should log STFT as well.

Hahah, I was thinking to myself, Bova is gonna want him to log stft . You know I ignore them, BUT, I had like 150 miles on my map before I did my maf cal the other day, so everything was pretty damn stable. I think my LTFT's are within 2 or 3%. I forget, but they're real solid. I did look at STFT's, but they bounce around a bit ("as they should" -Helpfile), so I don't get summing them with the LTFTs? Is that more important to do if less miles are on the map?

TIA

 

[bova80]

I only say it because some people don't like to wait it out before they start trying to calibrate after making a revision.

 

[Dot584]

I did log STFT and they were all around 0 because this was taken after about 65miles on the base stage 2 tune. So by only logging those PID's will it give me the volts in more increments? I did notice that in AT the volts in the log were sometimes different than the ones on the MAF chart and I was forced to choose the closest ones and then multiply. Is this what you mean?

 

[dougefresh_]

I did log STFT and they were all around 0 because this was taken after about 65miles on the base stage 2 tune. So by only logging those PID's will it give me the volts in more increments? I did notice that in AT the volts in the log were sometimes different than the ones on the MAF chart and I was forced to choose the closest ones and then multiply. Is this what you mean?

That's good that they were zero so you can ignore them, and it makes it a bit easier, especially your first time here. And yes, by only logging those PIDs you will get more volt datapoints, which will help you (a lot) in seeing where the breakpoints are.... that is exactly what I mean. That is also why I suggested running a few maf g/s tests, as this will help getting a clearer picture as well. You're catching on fast, and I give you serious props for taking the time to learn, and tackling the maf cal . That's probably the biggest learning curve to get though when you are starting out. Keep up the great work, and don't hesitate to post those maf g/s logs if you want some more input.

 

[Dot584]

Thanks for the help, I really really appreciate it and I will defiantly post the new MAF logs once I get at least 50 miles on this new MAP. I flashed it before I read what you said about the break points but I drove all day and there was no KR that I saw. Hopefully even with my inaccurate log it is still safe to drive? I can always start over from the base map I guess if that's necessary.

 

[bova80]

you'll be fine. if you aren't throwing a CEL then your calibration isn't that far off. and don't worry about partial throttle KR, you'll come to learn it means nothing.

 

[Dot584]

So these are after about 55 miles on my getto/first try tune. The LTFT's seem to be down a about half while at partial throttle but at idle they are back to -12 again. Also did I do the logs how you said douge?

 

[Dot584]

NVM I read your post again and I did a log. What I got is similar to the last 2 but with only LTFT, MAF g/s and MAF voltage. But once again idle is at -12 but partial throttle is no higher than -4.8. So does that mean my last tune was done right? or does tuning the idle require another step?