EFIE Schematic?

[Cburg]

Dear Forum,
Does anyone know of a good schematic for an EFIE for the oxygen sensor?
Thanks a lot!
Mike

[theholycow]

http://www.google.com/search?q=site%...avers.org+efie
4th result -> http://www.gassavers.org/showthread.php?t=8912 ->

Originally Posted by theholycow

I know I've found all of these here before but I'm having trouble digging them up again. I usually save this stuff when I find it but I can't find any saved copies either.

I did find this AFR meter on google:
http://www.scirocco.org/tech/misc/afgauge/af.html

I found this DIY PWM on google:
http://www.rmcybernetics.com/project...generator2.htm

Here's some EFIE digging...
http://better-mileage.com/memberadx.html
http://www.youtube.com/watch?v=PEHJ9te7gvk
http://www.esnips.com/doc/718eacd2-0...nhancer-Manual (or download at http://www.esnips.com/nsdoc/718eacd2...action=forceDL )

I wish I could find the ones that have been posted here before...I remember some pretty decent ones a couple months ago.

Note that the first EFIE link there is bad but the Youtube and esnips links are good.

[Cburg]

Hi HC,
Thanks for the info! Do you have any idea why the esnips circuit uses a 555timer and adds voltage to the output of the O2 sensor, while the poor man's circuit just adds voltage to the output of the sensor?
Thanks!
Sincerely,
Mike

[theholycow]

Sorry, I have no clue.

[GasSavers_BEEF]

the 555 timer will give almost a clock pulse. basically all you need to do is bump up the voltage to chance the AFR though there are limits to how much you can change it.

I would think that it is one of two things. either the system would like to see the pulsed signal but can handle a solid voltage instead or the 555 timer is just there so that it looks compicated and someone wouldn't try to replicate it themselves. many times companies put in stuff like that just so people won't try to copy it. they make it look complicated though it is not. there again, just a theory on my part (hypothesis actually)