When you change a value in the EPROM, and burn the new chip, the values in the BLM table are still the old values from before the changes, right???

Is it good practice to (somehow) wipe out the old learned values and drive for a while for the ECU to learn the new values??? (Or will driving overwrite the values without any coaxing from me)???

If so, how to erase the old values???

(Sorry if my terminology is off - still learning!)

 

You erase BLMs the same way you erase codes, just unplug the ECM fuse in the engine compartment.
And yes, i reckon it's good practice to do so after major changes, but if you only do a few tweaks at a time it is still relearning whether from baseline or not.
...ed

 

I just checked my timing and figured I'd reset the 42 error code (from the EST wire being disconnected) using that fuse you mentioned...But I can't find any fuse in the eng compartment...I finally just unhooked the battery ground...

This is an '86 Vette; but if the F-body has a ECM fuse, this should too...Where is it located on the F-body???

TIA!

 

F-bodys have it right near the battery in a single socket holder.

 

If your serious about soing chips the install a switch on the Orange Bat wire near the ecm. Also makes for an anti theft devise. The orange lead is the mainpower to the ecm, the pink/black just tells the ecm to wake up.