[Gmecm] Back to square one

[Robin Handley]

> What I can say with certainty is that flipping the bit to 1 BAR and
> connecting to a 1 BAR sensor produced poor idle and driveability in my
> car.  I had no desire to chase the reason, I simply switched to a 2 BAR
> sensor.  I valued the time spent more than the potential for education.

I've been comparing what values PROMgrammer shows for pressures (kPa), for
the same Sunbird.bin, but when the MAP sensor range flag is changed:

Some calibration values are approximately halved.
Some are identical.
Some are approximately the same.

So, PROMgrammer seems to be applying different scale factors/formulae, to
convert the raw stored value into kPa, for different calibration values.
Whether it is doing this when appropriate I just don't know. I had been
hoping that the GM programmers had been sufficiently clever so that raw
values (stored in the .BIN) would be appropriate no matter what sensor range
is chosen, but I'm beginning to wonder if this was wishful thinking. If life
isn't that simple (and I expect it isn't), then I reckon I've potentially
got a yucky job on my hands to try and work out what new values should be
used. This could be made all the more difficult if PROMgrammer's scalings
aren't right - as I could be putting in a perfectly sensible value of kPA,
which is then scaled to something stupid. :-( I'd be very grateful if
somebody could comment here. :-)

Dependent on what the expert response is, the option of buying a 2 BAR MAP
sensor is looking more attractive. Anybody know what a scrap one goes for?
Are they easy to come by?

The last option that I can think of is to find a set of calibration values
for $58 from a NA car. Anybody know if one of these exists? Were all Sys/Tys
Turboed?

Robin