85 ecm batch bank
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
85 ecm batch bank
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.
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.
Le Mans Master
Joined: Mar 2002
Posts: 5,889
Likes: 2
From: Castro Valley Calif.
St. Jude Donor '03 thru '26
The operative word here is definitively as opposed to an educated guess. You might want to try 3rd Gen DIY Prom Beach, those guys do a lot of work with '870 ECMs.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
According to this schematic of the fuel section of the 1226870 ECM:
http://www.exatorq.com/ludis_obd1/1227170sheet6.gif
Both banks and therefore all 8 injectors fire at the same time.
The schematic is for the 6 cylinder version, but Ludis says the circuit boards are the same.
Whatever happened to Ludis anyway? His site disappeared around 2002 or so. The above link is a mirror site.
http://www.exatorq.com/ludis_obd1/1227170sheet6.gif
Both banks and therefore all 8 injectors fire at the same time.
The schematic is for the 6 cylinder version, but Ludis says the circuit boards are the same.
Whatever happened to Ludis anyway? His site disappeared around 2002 or so. The above link is a mirror site.
Last edited by Cliff Harris; May 20, 2012 at 12:23 AM.
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
According to this schematic of the fuel section of the 1226870 ECM:
http://www.exatorq.com/ludis_obd1/1227170sheet6.gif
Both banks and therefore all 8 injectors fire at the same time.
The schematic is for the 6 cylinder version, but Ludis says the circuit boards are the same.
Whatever happened to Ludis anyway? His site disappeared around 2002 or so. The above link is a mirror site.
http://www.exatorq.com/ludis_obd1/1227170sheet6.gif
Both banks and therefore all 8 injectors fire at the same time.
The schematic is for the 6 cylinder version, but Ludis says the circuit boards are the same.
Whatever happened to Ludis anyway? His site disappeared around 2002 or so. The above link is a mirror site.
I'm not sure, but I need to know.... any clarification on this would be helpful.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
That diagram from the FSM really confuses things. It's not clear if the original link I posted is 1/2 of the injector driver circuit or not. I guess the only way to really find out is to get some photographs of the ECM internals.
I can't connect to the link tonight, though it worked fine last night. Anyhow, it showed one driver going to cylinders 1, 3, 5 and the other going to 2, 4, 6 (as I said earlier, the schematic is for a 6 cylinder engine). The basic circuit would have to be the same, as the connections to the injectors are outside the ECM.
It's possible that the FSM diagram is wrong. In my 1227165 ECM there is a circuit to measure the current through the injectors, so that might be where the connections to C1, C2 and D14 go. In the 1227165 ECM, D15 & D16 are the left and right injector banks.
I can't connect to the link tonight, though it worked fine last night. Anyhow, it showed one driver going to cylinders 1, 3, 5 and the other going to 2, 4, 6 (as I said earlier, the schematic is for a 6 cylinder engine). The basic circuit would have to be the same, as the connections to the injectors are outside the ECM.
It's possible that the FSM diagram is wrong. In my 1227165 ECM there is a circuit to measure the current through the injectors, so that might be where the connections to C1, C2 and D14 go. In the 1227165 ECM, D15 & D16 are the left and right injector banks.
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
The F-body guys are showing a single driver that powers both pin outputs for grounding the injectors. In otherwords, all injectors on the 85 are fired at the exact same time. Hence, it is not Batch Bank fire, but instead just Batch fire. (My terminology. 
)
Thank you !
) Thank you !
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