About to get tuned - logs

[texasboy21]

I purchased a PBD tune over the Labor Day sale to replace my canned SCT tune. I would like to take some logs before and after, but when I searched I did not find any DIY or sticky threads on what fields to monitor, correct/safe ranges, etc.

My goal is to:

1. Ensure my car is running as it should now with SCT tune (in the summer heat and humidity it doesnt feel as good as it did in March when I loaded the tune.)

2. Get some airflow, timing, etc. data to compare the SCT tune to the PBD 93 (and the PBD 93 to E85).

Any guidance on what to log and look for would be appreciated. I am familiar with data logging but not on this platform. Thanks!

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[Zinc03svt]

Ask your tuner what they want you to log. They should have a list of pids.

 

[BmacIL]

Ask your tuner what they want you to log. They should have a list of pids.

This.

Your tuner will give you a configuration file to log with and specific driving they'll ask you to do in order to get the logs they need. It'll be at least a partial throttle accel, some idle, and a WOT from low-ish RPM.

 

[texasboy21]

This.

Your tuner will give you a configuration file to log with and specific driving they'll ask you to do in order to get the logs they need. It'll be at least a partial throttle accel, some idle, and a WOT from low-ish RPM.

Thanks for that! I will most definitely send the correct logs into the tuner for them to make the appropriate changes.

What I wanted to do in the meantime was take some basic data from the car. In the Audi world we use "measuring blocks" such as 115 (actual vs requested boost), 020 (timing corrections per cylinder), 231 (low pressure fuel pump duty cycle), etc.

Unless you know what to look for and measure blocks to capture its all random. I was hoping for some guidance on what where to start.

 

[BmacIL]

Thanks for that! I will most definitely send the correct logs into the tuner for them to make the appropriate changes.

What I wanted to do in the meantime was take some basic data from the car. In the Audi world we use "measuring blocks" such as 115 (actual vs requested boost), 020 (timing corrections per cylinder), 231 (low pressure fuel pump duty cycle), etc.

Unless you know what to look for and measure blocks to capture its all random. I was hoping for some guidance on what where to start.

At a bare minimum:
Long term fuel trims (bank 1 and 2)
Short term fuel trims (bank 1 and 2)
Lambda (bank 1 and 2)
Knock sensor
Throttle position commanded
RPM

There's more, but log what your LTFTs are at idle, cruise along with lambda. Do a WOT pull from 2k rpm and verify no or very little (0.5 deg or less) knock retard. Those are some of the basic things that they'll want to see.

 

[texasboy21]

At a bare minimum:
Long term fuel trims (bank 1 and 2)
Short term fuel trims (bank 1 and 2)
Lambda (bank 1 and 2)
Knock sensor
Throttle position commanded
RPM

There's more, but log what your LTFTs are at idle, cruise along with lambda. Do a WOT pull from 2k rpm and verify no or very little (0.5 deg or less) knock retard. Those are some of the basic things that they'll want to see.

Awesome, this is exactly what I am looking for!

 

[v8hgt]

You want to see negative knock. This is good, as it means more timing is being commanded. Positive knock is bad. The only time you should see positive knock is during shifts if manual as the drive train is sloppy.

The fuel trims should all be targeting in all conditions 1.0. This means the tune is perfect. If short term is greater than 1.0 it means the O2 sensors are telling the ecu that the car is lean, as it’s closed loop the ecu commands more fuel be injected to maintain 14.3:1 ratio. If the trim is less than 1.0 then less fuel needs to be injected.

E. G if you get short term trim of 0.92 at idle the tune is rich by 8% in this state (temp/air temp/revs/load etc) the ecu compensates by injecting 8% less fuel than the map tells it to.

Trim of 1.08 means it’s 8% lean so 8% more fuel needs to be injected.

This is why your afr on the computer constantly moves about either side of 14.3:1 it’s always hunting and retrimming to maintain that ideal ratio.

When doing your log also log the battery voltage and note when the fans came on during the hot idle. Point this out to PBD. There will be a big voltage spike. Also log when the fans go off. If the short term trim goes lean when the fans are running point this out to PBD in the before and after tuning logs.

 

[texasboy21]

You want to see negative knock. This is good, as it means more timing is being commanded. Positive knock is bad. The only time you should see positive knock is during shifts if manual as the drive train is sloppy.

The fuel trims should all be targeting in all conditions 1.0. This means the tune is perfect. If short term is greater than 1.0 it means the O2 sensors are telling the ecu that the car is lean, as it’s closed loop the ecu commands more fuel be injected to maintain 14.3:1 ratio. If the trim is less than 1.0 then less fuel needs to be injected.

E. G if you get short term trim of 0.92 at idle the tune is rich by 8% in this state (temp/air temp/revs/load etc) the ecu compensates by injecting 8% less fuel than the map tells it to.

Trim of 1.08 means it’s 8% lean so 8% more fuel needs to be injected.

This is why your afr on the computer constantly moves about either side of 14.3:1 it’s always hunting and retrimming to maintain that ideal ratio.

When doing your log also log the battery voltage and note when the fans came on during the hot idle. Point this out to PBD. There will be a big voltage spike. Also log when the fans go off. If the short term trim goes lean when the fans are running point this out to PBD in the before and after tuning logs.

Excellent information!

Regarding the fans and voltage spike, why is that important info for the tuner to have?

 

[v8hgt]

They can see exactly when the fans run from the spike. Load goes on the alternator so the ecu has to open the throttle to maintain tick over rpm.

If your cai is open, the fans can cause it to lean out a bit

 

[Phils15GT]

How did you make out with the PBD tune? I just loaded in my PBD E85 tune on my 18 auto.. They said that no data log was required for a stock intake E85 tune. Loaded tune, swapped to E85 and they say its good to go. I drove the car around yesterday and it feels pretty strong. Only thing I noticed is a slight hiccup on the 2-3 shift under WOT. I am going to see if I can send them a log. The only mod is a Corsa extreme catback and e85 tune.

 

[texasboy21]

How did you make out with the PBD tune? I just loaded in my PBD E85 tune on my 18 auto.. They said that no data log was required for a stock intake E85 tune. Loaded tune, swapped to E85 and they say its good to go. I drove the car around yesterday and it feels pretty strong. Only thing I noticed is a slight hiccup on the 2-3 shift under WOT. I am going to see if I can send them a log. The only mod is a Corsa extreme catback and e85 tune.

Dont have my tune as of yet. Hopefully it will be in my inbox today.

 

[Zinc03svt]

Only thing I noticed is a slight hiccup on the 2-3 shift under WOT. I am going to see if I can send them a log. The only mod is a Corsa extreme catback and e85 tune.

If there is a hiccup/hesitation they have not cleared all the torque mgt/limiters. Logging only way to show it.

 

[Phils15GT]

Going to do some logs tonight, thanks

 

[AZ18yote]

How did you make out with the PBD tune? I just loaded in my PBD E85 tune on my 18 auto.. They said that no data log was required for a stock intake E85 tune. Loaded tune, swapped to E85 and they say its good to go. I drove the car around yesterday and it feels pretty strong. Only thing I noticed is a slight hiccup on the 2-3 shift under WOT. I am going to see if I can send them a log. The only mod is a Corsa extreme catback and e85 tune.

Must depend on tuner. I know I had to provide logs before tuning even started. Then many times through process.

 

[ENPhoto]

To add to this, (I think you can log these with SCT PID's)

Mass Airflow Period
Torque Source
Spark Source
Fuel Source
Mapped Point 0-26 Weight (if available)
Mapped Points OP Weight (if available)


If you are at all interested in the basics of what tuners do, look into the "Coyote Cookbook" (HPT and SCT) versions, by Don Lasota. I wouldn't buy the binded book, because the e-book is continually updated. It's a BASIC book, but is a good read for ~ $80

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