Blackrx7 did an ECU writeup and posted the following picture to show which wire on the ECU to ground.
http://www.1300cc.com/howto/how2/safc/ecu.jpg

Other forum members have been posting this link for the ECU grounding.
http://www.home.earthlink.net/~burntoast/3700.html
This describes the ground wire to be on the smallest plug, which is in contrast to the first diagram.

Can someone please clear this up?
Thanks.

 

I'll take a stab at this. If I'm wrong, I'm sure someone will correct me.

I believe that you are looking at two different grounds. The ground on Scott's site is for the ECU itself. The ground described on the earthlink site is the ground for the injectors that is supplied by the ECU.

You can redo both grounds if you want to- it won't hurt anything.

Dan

 

As per that second link, the ECU has four ground wires that all join together. You're adding a new ground wire (or two) to that joint.

 

The following is for a 86 thru 88 model. I think a N/T. But the grounds are the same. The picture of the plugs..........its looking into the back of the plugs with the connector on the ECU. Pay attention to that.

[IMG]The following is for a 86 thru 88 model. I think a N/T. But the grounds are the same. The picture of the plugs..........its looking into the back of the plugs with the connector on the ECU. Pay attention to that. [/IMG]

 

So as you can see, it's pins 2C, 2R, 3A, 3G that are your ground wires. If you read Burntoast's article, you see they are all spliced together about a half foot from the plugs. Not all splices are successful evidently, judging by the threads on this site.

NOTE: The grounds on a series Five are a bit different. If you own a series Five....ignore the above and look at your manual.

 

Ahhh, thanks for clearing that up gentle men.