DAM (Dynamic Advance Multiplier) sitting at .875

[Silinc3r]

So, may already know the answer but just trying to see what everyone thinks.

Removed my Megan Racing downpipe and headers due to cracks and installed Tomei Expreme header and a Tsuedo downpipe. I was already tuned for the previous parts so a tune shouldn't really be required. However, I did install a Perrin turbo inlet.

 

DAM has been sitting at .875 with no other issues. Just wondering if it might be gas related. Haven't used Shell as I normally do. Been running 93 Chevron. Again, car seems to run fine with great vacuum and hitting full boost with great AFR of 11.14 at WOT.

[ragman]

Have you reset the ECU to see if returns back to 1?

[Silinc3r]

Have you reset the ECU to see if returns back to 1?

 

I reset the max and min on the AP. And I have also unloaded and reloaded the map with no change. An actual unplug the battery reset I have not done.

[Tuning Alliance]

Are the DP's both catted or cattless? Also adding a turbo inlet will require an update to your tune.

 

Shoot us a PM if you want to discuss options.

 

-Brian

[solidxsnake]

A lot of times when your DAM step size changes from the standard step size (0.25), it is near impossible to get it to learn its way back up to 1. In those cases, it's quicker to reset the ECU and then go through a couple WOT pulls until it's back up (assuming you're not getting any knock).

[serx7]

If you've reflashed the tune you've basically also reset the ECU. Resetting the min/max on the AP (assuming you have DAM displayed as a gauge) doesn't do anything except reset the gauge display min/max values.

 

Try what solidxsnake suggested. IME you can just warm up the car fully, shut off the motor, reset the ECU (key off for several sec as directed by the AP), restart the car and then do a couple of part throttle boosted pulls. Assuming your tune starts DAM below 1, if you do a part throttle boosted pull for 3-4 sec starting above ~2500 rpm and keep boost above WG boost pressure (say 10-12 psi), you should see DAM increase to its max value of 1 during a single pull unless it encounters knock. If you aren't able to maintain a pull for 3-4 sec you might need to repeat the process 2 or 3 times.

 

Side note on AFR reading 11.14:. If you're using the AP O2 gauge, you're likely not seeing the true AFR under boost. For that you'd need a WBO2.

[Silinc3r]

If you've reflashed the tune you've basically also reset the ECU. Resetting the min/max on the AP (assuming you have DAM displayed as a gauge) doesn't do anything except reset the gauge display min/max values.

 

Try what solidxsnake suggested. IME you can just warm up the car fully, shut off the motor, reset the ECU (key off for several sec as directed by the AP), restart the car and then do a couple of part throttle boosted pulls. Assuming your tune starts DAM below 1, if you do a part throttle boosted pull for 3-4 sec starting above ~2500 rpm and keep boost above WG boost pressure (say 10-12 psi), you should see DAM increase to its max value of 1 during a single pull unless it encounters knock. If you aren't able to maintain a pull for 3-4 sec you might need to repeat the process 2 or 3 times.

 

Side note on AFR reading 11.14:. If you're using the AP O2 gauge, you're likely not seeing the true AFR under boost. For that you'd need a WBO2.

 

 

I'll have to give the reset a try.

 

I have been getting the AFR from the logs. I have an AEM wideband also. I guess I have forgotten that the log is reading an narrowband AFR vs my AEM wideband.

 

Here is a pull from tonight in 3rd gear just so you can see what I got going on.

datalog10.csv

[serx7]

You may want to hold off on trying the ECU reset.

 

From your log, it looks like the ECU is experimenting w/ adding timing back (you can see +0.35 deg FLKC applied bn 4k-4.8k at WOT which is a positive sign), -however- there's also -1.05 deg FLKC being applied b/n 4.8k-5.8k rpm. Assuming your tune uses default Fine Learning Retard Magnitude of -1.4 deg, it looks like the -1.05 deg FLKC started as out as -1.41 deg and the ECU has subsequently added back 0.35 deg. But it's still not a good sign to see DAM < 1 and the car is -still- pulling timing.

 

Perhaps you're running a little lean or are running a little too much timing in that area.

 

Do you have the ability to datalog the wideband? My AEM X-Series controller/gauge has a data cable attached, so I can datalog WBO2 AFR via Accesstuner Race on the laptop instead of using the AP. I do that any time I'm specifically looking for AFR issues, otherwise I just use the AP. In a pinch I've done pulls by datalogging w/ the AP while using my phone to record the WBO2 gauge display (making sure the tach is also in the frame), after which I correlate AFR to the AP log by matching up logged RPM to displayed RPM in the recorded video.

 

[Edit: You should probably add Calculated Engine Load to your log list, perhaps also Boost Error. If you're going to log/video record WBO2 AFR, you should probably add Commanded Fuel Final so you can compare Commanded Fuel Final to the actual WB AFR. You can probably omit Coolant Temp, it isn't really going to help w/ your logging sampling rate but you probably don't need to include it.]

[Silinc3r]

So I was doing some wiring last week and disconnected the battery. Car has been at DAM 1.0 since then. I had to disconnect the boost line that went to the Prosport sensor and wondering if it was leaking a little. So when I reconnected it, it had a better seal and DAM is all good again.