What are BLM's and should I reset Them?

What are the BLM's I seee that you can reset them in Freescan. I have done a lot of little mods too the car. Should I reset the BLM's? Thanks!!1

If you have unhooked your battery during these mods the BLM will reset themselves.
They are your computers version of an active memory.
It tells the PCM what it did in the past to correct a rich or a lean A/F ratio.
For that matter if they stay fairly close to 128 ( not 20 away)
and aren't split (ex. Left being 116 and the right being 135)
You should be ok.


Edit: here is a site that explains it really well.
Its about 1/2 down. (Introduction- Air Fuel Management.
http://members.aol.com/InjuneerZZ/ScanMast.htm

Here's a good sight to start learning about your pcm.

http://para.noid.org/~lj/