GM TBI info needed

[Steve Ravet]

Stowe, Ted-SEA wrote:
> 
> Hi.
> 
> I have an ecm/throttle body from a 1985 canadian sunbird.
> I am trying to figure out a little more detail on the cpu
> and what the ecm requires
> 
> the Serv. No. is 1226867        DJU
> 861611 M51197560

Have a look at Ludis Langens' WWW page for info on lots of GM ecms.  

http://www.cruzers.com/~ludis/

> 
> the eprom has on it "DJU 4085"
> 
> the throttle body has the following numbers
> 17085082
> 0385HSK2S
> 
> I do not know the VIN code of the engine, nor anything else about the car.
> 
> I am trying to figure out if it had an O2 Sensor and what/where the speed
> sensor was.

The Vss sensor probably was built into the IP cluster, driven by the
speedo cable.
It's a little metal paddle attached to the speedo cable, with some sort
of LED sender and receiver straddling it.  2000 pulses per mile.
> 
> also as I ponder over the chilton's book , looking at generic examples from
> '85
> 
> I see that there was an input from the brake pedal through the torque
> converter solenoid, C2 pin 19 ,I presume that was just an input 0 volts =
> brake pedal pressed ?

The TCC circuit works like this:  (from memory.....)

Battery voltage is applied to the TCC solenoid through a switch on the
brake pedal.  The other side of the solenoid goes to the ECM.  The ECM
applies ground to energize the solenoid.  The brake switch is used to
interrupt the circuit when you put the brakes on.


> 
> I suppose I can ignore the air conditioning inputs/outputs ? (C1 7,9,21)

If the ECM sees an A/C request it'll respond by increasing idle speed. 
If you aren't using them, tie the input to "always off".

> 
> what would the gear selector switch do ? (C2 pin 6) looks like it was
> grounded in some selector position, or positions ?

There is a Park/Neutral switch that tells the ECM whether the trans is
in gear or not.  There is some reason for implementing it, but I can't
recall what.  Lots of people wire it to "park/neutral".  Seems like that
may lead to stalling problems or something.

In 700R4 applications there is also a 4th gear input.  That tells the
ECM when the trans is in 4th gear.  It changes the TCC lockup schedule. 
Don't know if you have that or not.  It comes from a pressure switch in
the transmission itself.

I recommend calling Helm/GM and getting the real service manual for that
car.  It'll be very useful.

> 
> & finally, the 4 lines to the hei distributor, C1 10,2,3,19 ? were these
> inputs or outputs ??
> 
> thanks, this looks like it's going to be fun.
> 
> I am going to attempt to put this on a 77 mgb.

Keep us posted.

--steve


-- 
Steve Ravet
steve.ravet at arm.com
Advanced Risc Machines, Inc.
www.arm.com