As per the schematic, what we know about the Injectors on an 85 ECM is that the injectors are activated by grounding each bank seperately via solid state ecm activation. Each bank has its own driver output from the ecm for this. In otherwords Batch Bank fire.

What I do not know.... do the drivers activate each bank at the exact same time or does each bank fire at different times. I think just because there is a seperate driver for each bank, it doesn't necessaily mean they fire at a different time, hence this is what I am trying to find out.

Does anybody know "definitively" how the 85 ecm works ?

Thanks.

 

According to the schematics that Ludis put together, it is batch fire. All eight injectors fire at the same time. I have no reason to doubt the work Ludis did.

RBob.

 

I do not understand. The schematic I have shows the ECM has two different driver outputs for the injectors. One for each side of the motor. (1,3,5 & 7 and 2,4,6 & 8)

Maybe he has a comprehensive internal ECM schematic ? Would love to see the logic that closes these ECM outputs. They may both be at the same time, but would like to see the on-paper logic that shows this.

 

www.exatorq.com/ludis_obd1/schematics.html

See the 1227170 ECM, same hardware. You're welcome.

RBob.

 

a lot(and by that, i mean all) of the 60V6 MPFI applications are setup the same way... 1 driver controls 2 pins.

 

Okay... thanks guys.

 

Some time ago I lost a bet on that one, the '870 TPI ECM along with the MAF 60V6 MPFI ECMs ('7302) have two injector drivers. Just that they are fired together. Check out the schematics I linked too, they are handy to have.

RBob.

 

gah, other than the fiero, i forgot there were even any 60V6 MPFI applications that were C3. for some reason i thought the 2.8 F-bodies used a 7730 or similar.

http://www.exatorq.com/ludis_obd1/1227170sheet6.gif

i see it, 1 actual control circuit controlling a chain of transistors... i guess it would be more accurate to say that it's using a single injector "channel" to control all of the injectors.

 

Only the '90-'92 3.1l f-body cars used the '7730.

RBob.