HC sensing

[Scott Shotton]

peter paul fenske wrote:
> 
> HI Bruno
> 
> Well the smog tests look fer 1 part per million to a max of 500 part
> per million where they tow the car
> 
> Practically without cats I would say 100 ppm to 800 ppm
> 
> gl:peter


I guess that would depend on your states emission standards.  Illinois
allows no more than 220ppm HC back into the 80's.  (I'm not exactly sure
of what year).  After the converter, a late model vehicle running
properly can have near 0ppm.  A partly clogged fuel injector causing a
lean miss still could inject enough fuel to change this number by
several hundred, even with a good cat.  Long duration cams increase HC
at idle tremendously.  And the list goes on.

I guess it all depends on the application.  Be a little more specific
and I can provide more information.

Scott