legacycentral bbs

I wondering if it'd be possible to remove an essential component of the ECU and build it into a hard plug-in box that has a connector under the dash

The idea is that even someone who was experienced with hotwiring cars would not be able to start the car, since the computer would be non-functional.

So you could remove that hard plug-in box when you parked the car?

Sure. There are several fairly accessible important pieces on the motherboard. The ignition output transistors come to mind; or maybe the injector driver transistors. Or the fuel pump driver transistor. Lots of transistors.

Exactly.

That would make it basically impossible to steal.


Im considered tho, that if you removed a piece like that, that it just might fxck the ECU if someone did try and hotwire the car

Nah; most likely it'd be okay. It might throw a trouble code, depending on how the monitor circuits are wired.

Hmm

Well, I suppose I'll crack it open and see what's in there that I can relocate.

What year is your car and what transmission and engine does it have?

It's Gary's 92 4EAT SS

All should be stock except IIRC, he swapped in the tranny from a regular turbo legacy when the other one gave up the ghost.

If you pop the cover off the ECU's case (four screws; one in each corner), and look at the top of the circuit board (the side with almost all the components) such that all the markings are right-side-up, there's a 10-pin single-inline-pin chip on the upper right of the case. If you remove the clamp holding it to the side of the case (one more screw), you should see that it's a Hitachi 4AC14. I believe this is the chip that drives the four injectors.

When you mount it remotely, be sure it's mounted to a decent heat sink. Use heat sink compound on its mounting surface too.