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Re: 4000 CS Turbo Quattro

Martin Pajak wrote:
> I would like to know what was done to provide the enrichment during high boost?
> I always thought the Oxygen sensor would be too slow to adjust the mixture this way.
> Detailed description would be apriciated.
> --
The O2 sensor is extremely fast.  It's an air/ion exchange battery, and
it is very sensitive and quick. Of course, it's location directly
affects how fast the computer can see the gas from the engine.  My
sensor is right after the turbo, about 8 inches from the engine. The
computer is quick also to notice the changes, but takes a second (ok,
milliseconds) to re-map the change in 02 sensor voltage, and then
convert D/A to adjust the current to the DPR, but the DPR is
electromagnetic.  First the field has to be re-saturated, then it
responds to the change in current.  By this time, MANY revolutions of
the engine has taken place.  Are you asking for a schematic for my
revised DPR driver circuit?  It provides a similar 10mA boost in DPR
current to the normal CIS-E, but I enrich a little more due to the
higher volume of air going through the engine.  I can still monitor O2
sensor voltage to see if i'm running lean at boost, and i'm still on the
rich side(at boost).  like to keep it that way too.  nicer on the valves
i hear. . .
Chris Locke 86 4kcstq