[Diy_efi] Making a fake O2

[Daniel R. Nicoson]

I've been watching this thread over the last few days.  People are debating
the safety of the stock maps with 02 faulty but no one has mentioned that
the engine in question is no longer stock.  Marcello mentioned that his
friend "only made a few changes" (eye-roll) meaning to me that probably the
friend put together a parts combination far from stock.  Most likely higher
compression and a more aggressive cam.  Those two possibilities alone
probably would make the stock maps irrelevant or at least "not safe".
Considering how much $$ most people typically throw at a motor when they
"make a few changes" I would proceed slowly and work to develop new maps.  I
think Marcello realizes this and hopes his friend will keep his foot out of
it until he gets home to work at the problem logically.

My experience is with Ford EEC's.  I know when I "made a few changes" the
EEC was totally confused because my parts changes had taken the range of
operation well beyond the stock limits of compensation.

Good discussion.

Dan Nicoson


> -----Original Message-----
> From: diy_efi-bounces at diy-efi.org [mailto:diy_efi-bounces at diy-efi.org]On
> Behalf Of Steve Ravet
> Sent: Tuesday, May 31, 2005 12:36 PM
> To: diy_efi at diy-efi.org
> Subject: RE: [Diy_efi] Making a fake O2
>
>
> I was going to refer to the EFI testbench that Bruce built.  My
> recollection is that he used a 555 type circuit to generate an O2
> signal.  There's not really any mention of it in the article, but I'm
> sure the details are in the archive.  I think for some computers this
> worked OK, for others that expected to see more correlation between
> pulsewidth and O2, it didn't.  Anyway, go to the gmecm page, projects,
> then ECM testbench for the ascii version of the article.  The MS word
> version is probably gone for good.
>
> --steve
>
>
> ________________________________
>
> 	From: diy_efi-bounces at diy-efi.org
> [mailto:diy_efi-bounces at diy-efi.org] On Behalf Of Bret Levandowski
> 	Sent: Sunday, May 29, 2005 11:16 AM
> 	To: diy_efi at diy-efi.org
> 	Subject: Re: [Diy_efi] Making a fake O2
>
>
> 	Actually, it is not 'impossible to fool an ECU with a constant
> or switching voltage source'. There are two companies I know of (in the
> states) that have developed a plug-in replacement for the O2 sensor on
> numerous vehicles (mostly OBD II) that generates a 'proper' signal.
> These are used in instances where inj size was increased or a turbo or
> screw-charger was installed. Some also did require a flash of the ecu.
>
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>