always faster

Probably a easy one but after a pcm tune do i need to do some miles so that the blm would learn everything before logging it to see if everything is fine?

or

I can insert a pcm tune and log it right after(ex:idle)?


Thanks

Injuneer

Its best to drive the car the way you normally drive it for a few days, after resetting the PCM or programming it. The idle cell (16) and the cells used frequently will stabilize in a matter of minutes. But the seldom used cells may take quite a while to develop fully.

sbs

Yes you can log it right away.

The log itself will show you when the BLMs have stabilized, which takes a matter of seconds unless the tune is way off. Even then it's only a matter of tens of seconds.

Logging can accelerate the learning, as well, since you can monitor the cell and BLMs while driving in order to use each cell enough to reach steady state.

mrmint69

If you went out and loaded a tune and then immediately made a 1/4 mile run you would probably see a different if only slightly what the car would show after maybe a few miles of driving. Its amazing how quickly the car can adjust and how many calculations it can make in only a second. I will at least make a 5-10 minute drive before hooking up the laptop at different rpm and speeds to see whats going on. Good debate that i will stay out of.

always faster

Im maybe asking too much but do you got any idea on how much miles(approx) would it need to be drove?

Thanks

Injuneer

No I don't..... people have sent me hundreds of data logs to look at. Typically, they have reset the PCM. You can watch Cell 16 develop quickly, over a matter of minutes. In their single drive, they've maybe operated in Cells 6, 10 and 14, sometimes only for a few seconds. They have no time at all in the other cellls, so the data is useless. I'd prefer to see a data log that's got a few days of "normal" driving on it. Apparently I'm alone in this belief, but after doing this for 10 years, and probably looking at well over 1,000 data logs, I just feel I can provide more useful insight into the problems if the PCM has NOT been reset recently. Take it for what its worth.

A few days of "normal" driving.... maybe 100 miles???? Don't know.... I just look at the logs, I don't know the history of the car between the last reset and the data log. But I know when its just been reset, and I'd prefer not to be sent those logs.

sbs

There's no such answer. Depend on your drivetrain, your tune, your driving, the weather, phase of the moon... Just turn on the datalogger, and drive it until each cell has stabilized.

But you don't need to stabilize every cell in order to improve the tune, anyway. Drive it with logger on, then adjust the tune only for those cells where the BLMs have stabilized.

mrmint69

I will be sending the datalog to the programmer so he can tweek it so i figured it would be best to drive it a few days. I will probably check tomorrow to see if anything is out of the ordinary. It would depend on the individual and the circumstance how long it truely takes. I think everyones right.