Programming 101

[Bruce Plecan]

I'll take bets that some folks were wondering if it was over, HEHEHE.
Nope, just cranking up on the bench stuff..
For those of you new to the show, please consult the archives about
all related matter before trying to use this information.  Again first and
formost this is for educational purposes, and may be illegal depending on
where you live..........

While tinkering with the O2 sensor design I've noticed something.
If running closed loop at idle, and if too rich the BL+INT numbers
start to drop, BIG news right,  well once they hit the bottom of their
limits, the idle goes Open Loop.  Then given some time with a
lean O2 they recover, and the system goes closed loop again.

If you want to maximise the ecm's control of idle then use the info.
Carl shared the other day, and using an entry of 05 at $2A0, and
00 at $2A1, will work just fine, for rpm entries.

But, how do you shut off that darn EGR when doing initial calibrations.
Well, that is a chore, but setting $1BF to 00, $1B8 to FD, and $1B9 to FF
will do very nicely thank you very much.
     ALSO BE ADVISED, you can have the EGR applied at idle.
Makes for a lousy idle.
    The ecm looks at say an idle value of .36v TPS.  That might also
be or very close to the min EGR, so it might hunt between being on +
off.
    Depending on the calibration you may or may not have to be moving for an
EGR apply so if at all in doubt use a LED with a 1K
resistor, and see if the EGR is getting an apply signal at idle, if
you have an idle problem.

If you have comments please feel free to e-mail me at nacelp at bright.net
don't quote me the whole text, I get bunches of mail a day and don't
need editing all the replies.
If you take issue with something I say please e-mail me off list, and
I and the staff will research the problem.
Cheers
Bruce    Working on having the bench ecms give off a soft orange
              glow...........