First Attempt at Tuning MAF on LS7

[c4love]

Hello Tuners looking for advise on my first Data log trying to dial in my MAF after changing to ported intake NW 102 and CAI Varram system. I am attaching my log if someone doesnt mind taking a look at it and tell me what im looking for what I did WRONG and whats right?

I know I got some logging done on MAF Hz just not real clear on what the data is telling me and if the data logged is any good. What am I looking for exactly in those cells when logging to know its good data?

ANY HELP im grateful for thanks all.

[5FDP]

Are you using a AFR or lambda error for tuning or fuel trims?

The AFR error would tell you exactly how the tune looks, no need question it if you have one setup right. It's going to tell you exactly how far off your commanded to actual AFR is and give you the data to adjust the MAF curve with. Overall the trims don't look horrible, still a little bit rich as it's pulling fuel still.

Also looks like you have a cat diag test still active, you may want to disable that if you removed the cats.

[johnny_boii]

Add Burst Knock/Knock Retard and Injector PW Bank 1 & 2 to your channels.

[c4love]

Thanks for the reply 5FDP - I have a wide band setup and the AFR Cmd so thats what I was using. And yes I do still have factory CATS on the car for now and you are correct that was active. But about midway through that log I put the car into Open loop and then took it back to closed loop in real time via the scanner. Im sure you can see that in the log if you watch all the way through. When I went open loop the RPMs started hanging alot higher and would not smooth out until dead stop a few seconds later.

That is the main thing I noticed since the parts changes is the idle hanging alot more coming to stops and shifting between certain gears.

[c4love]

Add Burst Knock/Knock Retard and Injector PW Bank 1 & 2 to your channels.

I will add those Johnny an do some more logs thank you for the advice!

[c4love]

I have Injector Pulse width already being logged in my Channels unless you are referring to Averages? I did add the burst Knock as request. thanks let me know.

[c4love]

Not able to log Injector Pulse widths doesnt give me the options when I click the gear and narrow down my options it wont log that parameter.

[c4love]

So I have included the injector PUlse options screen shot and the AFR error from my log file I attached. I dont know what the numbers are really telling me or how to read this? Can anyone break it down hooked on fonics style ROOKIE #NOOBE TUNER.

Thanks
Chris

[5FDP]

If you don't click the gear icon and just right click add channel it will bring up everything. Injector pulse width for both banks should show up, then it would also populate injector duty cycle if you are logging it.

For the MAF error, if the graph is setup correctly the numbers shown are how far off the MAF curve is in a percent. If it was showing all negative numbers it would be removing that amount from the curve to fix the fueling. The MAF curve must be kept smooth, so if you apply the data and it creates spikes or dips you'll need to address that. Sometimes using the paste special by half is a good idea and hand smoothing.

[c4love]

Hey guys thanks for all the help so I have applied my first adjustment to the MAF. Def is helping!!! Running much better couldnt have got this far with out you.

So question! Im still occasionally getting a surge in RPMs sometimes when coming to stops instead of the car returning to base idle like it should. This only happens maybe 15% of the time so out of 10!stops maybe 1 or 2 times max. But when it does the rpm will jump up to like 2 to 3k an hang until im completely dead stop then will come down SLOW to base idle. It really sucks when it does this! Coming to a stop an your car sounds like its reving it self up lol!

Any ideas how I can address this in the tune? What should I look at or where to start? Again doesnt happen often but when it does it sucks. Also i noticed seems to only happen once car reaches FULL operating temp. If its cold doesnt ever happen.

Thanks
Chris

[c4love]

Hey guys should I be trying to Dial in my map or VVE first before the MAF tuning? I have read so many differwnt things on this. Confused now.

Thanks

[5FDP]

Doesn't matter really, either or.

The MAF is generally faster to dial in a GEN 4 vehicles with VVE.