Bench racing ecms Even if ya hate 101 please read

Bruce Plecan nacelp at bright.net
Mon Jun 15 21:15:13 GMT 1998


I just put the hammer, and nails away from nailing the ecms down.
Actually coffee cup hooks, and rubberbands.  Got a 1'x2' sheet of
particle board, 1/2" thick, and the ecms tied to that via the rubberbands.
So some barrier strips and we get to fire up the
soldering iron (well actually crimper).

Here is what I have, and what I think I need, any thoughts comments
appreciated.

For a general representation of ecms, I have a 148, 165, 730, 747,
plus some misc ones, for generating smoke..  If some one stumbles over a
749, or a flash prom type give me a holler, on the flash prom
type would I need a set of ecm connectors also, unless they are the
same as a 730 (three. one yellow two black).  Also on the flash a
v-8 version, please.
  I have the two+three ecm style connectors
A dual trace o-scope, calibrated with matching sets of probes
A frequency counter
An OTC Scanner
A Linder Scanner
A 50% dwell frequency generator for VSS,  hopefully this will work,
    and not have to bother with Buffer/amp, or DRAC..
A rpm signal generator, but have to work out an interface to module
     is a transformer necessary?.  Ya think just a 1.2v DC pulse would
    fire the module?.  Use a monstable 555 for the 1.2v, and then
    an adjustable astable for rpm?.
Some 100 ohm resistors for like charcoal canister/ EGR solenoid
    loads.
When doing ecm comparisons was going to use a common ground
    for the ecms, and one for the sensor grounds, once ecm to supply
   +5v for sensors.
With as much talk as the O2 being handles as a switch crossing the
    .44 as a O2 sensor crossing count was thinking of a divide by
    rpm signal source for generating a 0-.8v for O2 input????....
Then use a divide by for a map voltage off the egr apply to get
    an AFR change with egr applied.

Things I don't have a clue about yet:

Generating a MAF (hot-wire, hot-foil) type of signal for the ecm.  So far
got a shop vac. for generating flow across an actual sensor.

Was going to use pots for MAP/TPS/Coolant/IAT.

Not worried about A/C apply or P/S stuff.

Was going to try things with no IAC's, then if problems just dummy loads.
If reoccurring problems then use some TB's with IACs

12v lawn tractor battery, and circuit breakers.

Did I miss anything?.
Cheers
Bruce

How hard would it be to come up with a Laptop program for an actual
run/recording of vehicle?.  Then run some opto-isolators for triggering
rpm/vss/map/maf/iat/coolant temps for the bench stuff?.  Actually
would someone volunteer for doing this.....




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