No subject

Thu May 30 05:48:45 GMT 2013

and 2 ATM. The 1 ATM goes from 0 - 100 kPa, the 2 ATM goes from 0 - 190.
I don't remember the voltage ranges offhand.
> 	Throttle Position switch - TPS

Just a pot with a 1k pullup in the ECM. A/D is on a 5.1 volt reference.

> 	Engine rpm

Determined from the pulse width of the REF signal, which is either
based off a crank trigger or a distributor pickup. 

> 	Engine coolant temperature

The ECMs I've seen have the ability to switch between a 348 ohm and 
~3k internal pullup. The sensor used in not linear, so an internal
translation table is required in the PROM.

> 	Manifold air temperature - MAT

Another resistive sensor with a 1k internal pullup. 8-bit A/D again, too.

> 	Electronic spark control (knock sensor?) - ESC

Black Magic. :) The ones I've looked at have a circuit on a ceramic
substrate in the MEMCAL that does the filtering/level triggering and
then sends an EST signal to the timing logic. If you're looking for
a knock indication, watch EST.

> 	Idle air control - IAC  (?)

Stepper motor! Tables in the PROM determine the output to the stepper.

> 	Ignition voltage

Nothing in the PROM determines this, from what I can see.
> and for:
> 	Stoichiometric & Linear Lambda

Gonna have to be a little more specific here. The PROM holds a multitude
of VE and AFR Tables/Constants.

sdbartho at

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