Here is how you replace the ECM in a 1990 E350 with 460 EFI engine.

The actual computer lives in the passenger compartment. It is under the heat exchanger box for the heater core and AC core.

First, disconnect the battery. Then you can proceed with the actual replacement.

To start with, you must disconnect the connector to the computer, which is located in the engine compartment, underneath the blower motor.
To get at it, you must remove the air cleaner assembly.

In this photo you can see the connector directly behind the air intake pipe. The computer interface goes through the firewall. A 11mm socket is needed to remove the bolt that holds the connector to the computer.


Here you can see the connector unplugged:


Once unplugged, you can move inside the cabin and remove the computer.

It's actually not necessary, but removing the cosmetic cover that covers the heat exchanger box makes things easier. It is held in place with two phillips-head screws.


Note the placement of the ground strap. It must be returned to its position so it contacts the metal frame of the dash on re-assembly. This ties the computer chassis to ground.




With the cover out of the way, you can easily see the one single screw that holds the computer bracket in place. Remove it, and keep track of the ground strap.




Remove the old computer from the plastic cover. It simply snaps in and out. When the computer is out, slide off the bracket off of the old computer and onto the new computer, and then snap the new computer into the plastic cover. Also transfer the gasket from around the connector to the new computer.



Make sure your new computer's part number is the same as the old one.
Attachment 282562

Full-size pictures here:
https://imgur.com/a/ii3YD2h

 

Good info, thanks.

 

This is very helpful information.
Now, I'm wondering about part numbers.
My ECM part number is E7TF-BV1B.
When I search for it, I usually find the same number without the 1 (BVB) listed for the same year, model, and engine.
I also see ones with numbers and letters before the BVB.
Is there any difference or is they either shorthand for older items and long hand for newer remanufacturing?
Or, should I be hard restricting to the exact part number as original?

 

This is very helpful information.
Now, I'm wondering about part numbers.
My ECM part number is E7TF-BV1B.
When I search for it, I usually find the same number without the 1 (BVB) listed for the same year, model, and engine.
I also see ones with numbers and letters before the BVB.
Is there any difference or is they either shorthand for older items and long hand for newer remanufacturing?
Or, should I be hard restricting to the exact part number as original?