How To Datalog Using Your V3 Accessport
WARNING: REFLASHING AN ECU MAY VOID MANUFACTURERS WARRANTY, AND IT IS INTENDED FOR OFF ROAD USE ONLY, THIS IS INTENDED TO BE A GUIDE TO WALK YOU TO THE PROCESS OF LOGGING AND TUNING, TURBO TEK TUNING WILL NOT BE HELD RESPONSIBLE FOR ANY DAMAGES TO VEHICLE OR ANY OF ITS COMPONENTS AS A RESULT OF THIS FLASH, PLEASE MAKE SURE THE VEHICLE IS IN PERFECT HEALTH BEFORE ATTEMPTING TO DO THIS. PLEASE READ INSTRUCTIONS BELOW CAREFULLY. PLEASE OBEY ALL TRAFFIC LAWS, WE ARE NOT RESPONSIBLE FOR ANY ACCIDENTS, CITATIONS ETC. DO THIS AT YOUR OWN RISK!!! PLEASE BE SURE TO VIEW OUR TUNING CHECK LIST TO ENSURE YOUR VEHICLE IS MECHANICALLY READY FOR TUNING. http://www.turbotektuning.com/dyno-tuning-checklist/
Setting your Accessport and your vehicle for tuning.
Download the most recent version of Accessport Manager, connect Accessport to computer and ensure that there are no updates. If your Accessport is in need of updating, proceed through the steps on your screen to update your Accessport. Once the accessport has been updated proceed to copy the base calibration sent to you by us to your Accessport.
Connect Accessport to vehicle and proceed to reflash (NOT REALTIME ) your initial base calibration to the vehicle.
If at any point in the flashing process a vehicle communication issue occurs “DO NOT TOUCH THE IGNITION!!!!!!!!!LEAVE IT ALONE; DO NOT SWITCH THE CAR TO OFF!!!!!!!! Simply unplug the hand held from both the obd port and usb then reconnect the obd port followed by usb and repeat steps to flash map. , Or restart computer if needed and begin to flash the map again!!!!! IF YOU SWITCH IGNITION TO OFF YOUR ECU COULD BRICK” Fortunately the accessports are equipped with a recovery method which allows you to restore the ecu if needed with ease.
Now it’s time to set up [parameters for logging, because every vehicle is different with your base calibration you will be emailed with a list of all the parameters that need to be configured. A step by step video can be found by visiting http://www.turbotektuning.com/etuning/
The Logging Process
Start Vehicle and allow the vehicle to reach operating temperature, if the vehicle is already at operating temperature after your reflash, allow the vehicle to sit stationary for about 2 minutes to allow some learning to occur. l
Proceed to your destination where the logging will be taking place such as a dyno, track etc.
For best results begin logging from 2400 rpms and rev to as close to redline as possible in the gear you were instructed in your email, before doing your pull click center button on your Accessport to begin recording the data. When you are done doing your pull please press button again to stop the logging process. During the logging process, you will collect data for 3 conditions.
- Idle once vehicle reaches operating temperature (60 seconds of data)
- Cruise, low load normal driving conditions (120 seconds of data)
- Wide open throttle (2400 rpm to redline) Typically performed in 3rd or 4th gear depending on your vehicle.
Once this is completed, you are now ready for a calibration revision, Connect Accessport to Accessport Manager, extract your datalog and send your recorded datalog to firstname.lastname@example.org With every log emailed, please email drivers and passengers weight, as well as outside temperature and tire size.
Repeat this process until your vehicle has been completely calibrated, please allow 24 hours between logs unless an e-tune appointment has been scheduled. In most cases we find that our clients will log on their way to work and on their way back home.
For more information and to learn how to utilize other features on the Accessport please feel free to visit the Cobb FAQ section at https://cobbtuning.zendesk.com/hc/en-us
After the tune
2015 DIT WRX – DAM and Knock Corrections
The newer DIT car’s (direct injection turbo – 2015+ WRX and 2014+ FXT) strategy is a bit more reactive. This is intentional and is expected since “premium” fuel is not required on the DIT vehicles. The strategy has changed and is comparable to what may have been seen as Fine Knock Learning in the earlier non-DIT cars may now result in a drop in DAM in the DIT cars. It shouldn’t be surprising to see a drop in DAM on the DIT vehicles (as it is on early cars where DAM being less than ideal is an indicator there is an issue) especially running lower octane fuels. How long the DAM takes to return to 1 is not indicative of how serious the knock event was and does not mean the car is still knocking. In order to advance the DAM on DIT vehicles, you have to drive in specific load/RPM ranges without knock. Determining whether there is a a potential issue on a DIT vehicle require considering how low the DAM has dropped and what other knock responses ( Knock Feedback Correction and Fine Knock Learning) look like overall.
Hopefully this post can help ease some concerns when you see those values under the knock parameters. If you think your vehicle might be having some negative issue mentioned above, feel free to contact us and we can review datalogs, help troubleshoot, and answer any questions you might have. Also check out Cobb Tunings knowledge base for additional technical information on all things COBB. If you’re interested in learning more about Subaru Knock Monitoring.
Subaru knock detection is like using a large net to catch fish. You’ll definitely catch what you want to catch (actual knock) but you will also catch what you don’t want (false knock). If you used a small net, you would get less false knock but might actually miss actual knock. It’s a compromise. Be sure to look at the entire picture when trying to determine whether there is an issue.
General Guidelines for Monitoring Knock on a Subaru (non DIT Cars)
(The following does not apply to any of Subaru’s many newer DIT [Direct Injected] platforms)
The key when analyzing data logs is to keep in mind that the knock detection systems on these cars is not overly sophisticated and can report knock events when no knock has occurred. This is fairly typical at lower load or with bigger throttle changes. Also, some occasional small corrections can be normal and do not necessarily indicate a problem. Some general things that I look for that may indicate that a car has a knock issue to be addressed (based on logging):
1. Feedback knock correction or Fine knock learning -4.2 or worse at low loads (i.e. cruise/low throttle situations).
2. Fine Knock Learning of -2.8 or worse during wide open throttle (WOT) run.
3. Fine Knock Learning of -1.4 if it consistently covers a large portion of the WOT run (indicating multiple cells involved)
4. Feedback Knock (-1.4) in the middle of your WOT run that is fairly consistent run to run, but does not start near when you mash the throttle. The first time it drops (ex. goes from 0 to -1.4) is when the knock event happened for feedback knock – the rest is it just ramping back to zero (unless it drops again).
5. Feedback Knock of -2.8 or worse at WOT if not due to mashing the throttle.
6. If your dynamic advance multiplier (DAM) drops from 1.0 (for 2.5L Subarus) or 16 (for 2.0L Subarus). Keep in mind that some maps start the DAM at a lower value when you reflash or reset the ECU and this is normal and not a cause for concern – will eventually learn up to its max if all is good.
Boost Creep Issues by Lance Lucas ( Cobb Tuning )
A definition of Boost Creep, as provided by Garrett:
“Boost creep is a condition of rising boost levels past what the predetermined level has been set at. Boost creep is caused by a fully opened Wastegate(s) not being able to flow enough exhaust to bypass the housing via the Wastegate(s) itself. For example, if your boost is set to 12psi, and you go into full boost, you will see a quick rise to 12 or 13psi, but as the rpm’s increase, the boost levels also increase beyond what the boost controller or stock settings were. Boost creep is typically more pronounced at higher rpm’s since there is more exhaust flow present for the Wastegate(s) to bypass. Effective methods of avoiding or eliminating boost creep include porting the internal Wastegate(s) opening to allow more airflow out of the turbine, or to use an external Wastegate(s).” (http://www.turbobygarrett.com/turbobygarrett/boost_creep)
Testing conditions for the below graph:
- Weather: 14 degs F, 30.62 in (15.039 psi) atmospheric pressure, 88% relative humidity.
- Vehicle and modifications: 2013 STi Sedan, COBB Catted Turboback Exhaust, COBB SF Intake/Airbox, COBB 1000cc Fuel Injectors, DW65c Fuel Pump, COBB/LPC FPR Upgrade Kit (last three modifications do not impact boost levels observed; they only serve to provide adequate fueling during the scenario).
Boost creep cannot be eliminated by:
- A 3-port boost control solenoid
- Tuning changes
Boost creep is dangerous because:
- It can exceed the factory fuel system’s capacity, meaning that dangerously-lean air-fuel ratios and engine damage can result.
- Excessive boost can cause detonation that cannot be effectively controlled with the factory ECU’s normal response methods (reduced timing).
- If extreme detonation has been observed, from poor fuel quality or excessive boost, for example, one of the factory ECU’s methods for protecting the engine is to lower boost to the mechanical minimum. When the system exhibits excessive boost creep, this is no longer possible and engine damage is likely.
Boost creep is undesirable from a tuning perspective because:
- The calibrator has little/no authority to control boost levels throughout a large part of the run.
- Highly variable boost response depending on environmental conditions as system transitions below/above wastegate flow limit thresholds.
- When the wastegate’s flow limit has been reached, exhaust gas back pressure will undesirably rise (inefficient, causes detonation threshold to rise).
Boost creep is most likely with:
- Low ambient air temperatures and high atmospheric pressures (low-lying NW and NE regions are most affected, see purple within marked areas of US elevation map). (http://weather.unisys.com/usgs/3sec/index.php)
- Many airflow modifications, such as upgraded turboback exhaust, upgraded intake, upgraded turbo inlet, etc.
While doing software testing on the dyno last night, I couldn’t pass on the opportunity to make some power runs under the extreme cold weather we’re having. The PNW is currently in a severe cold-snap and ambient temps were around 16 deg F last night….and barometric pressure was reported as 14.94psi 😛 FWIW, the SAE dyno correction for the weather conditions was roughly .905 — really good, in other words.
Even at 0% WGDC, boost is completely out of control. The actuator is unable to hold boost below 10psi for basically any part of the run with a peak of 18psi at 5200 RPM. This was good for ~322whp, which math says would have been around 110% injector duty cycle if my car didn’t also have injectors/pump upgrades.
These WRX and STI boost creep (or uncontrollable overboosting) issues can be common in extreme cold weather with high flowing intake or exhaust parts. The best resolution is an EWG (external wastegate) and a custom tune. Alternatively, you could re-install the factory airbox and factory catback to help control boost better.