This is one of those "Sounds too good to be true" devices. Has anyone tried this engine computer module chip? Did your engine survive and/or was there noticeable performance improvement?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2427920577

I think it's just a diode or some such thing, that fools your computer into thinking the engine is cold via O2 sensor wire, and keeps the fuel mixture rich, like it is warming up. That may not be entirely accurate but is the jist of it, I would never put one on my vehicle, it is not good to run rich all the time.

I think you nailed it, two leads in, two leads out... can't do too much ingnition "mapping" without any brains! Seems like just like any engine, make her breath in better, breath out better and you are halfway there... what kind of computer chip does and E have? They had a chip for my old BMW, wonder if a similar one is avialable for an E...