I am in need of a ECU for my 1982 928. Anyone have one they would like to sell. Car is sitting dead at my work, hated to leave it there. Thanks in advance Brian

 

How are you sure its ECU? Rare failure point for 82.

 

I have no negative pulse at the injectors, Checked ground continuity from ecu harness and it is good. Any other common things to check? Thanks Brian

 

Are you getting full battery voltage at the CE panel, Brian? Ground wires, believe it or not, are deteriorating on these old cars, generally there is a gray strip of corrosion, sometimes under the plastic. Low voltage / some relays don't actuate.

Red bat wire, little one, feeds the ECU, check its cleanliness.

What is condition of injector relay? It can be jumped with a 3-ended wire. Its a common failure point.

Also, a short in one injector boot will take them all out. You can disconnect ECU harness connector and one injector plug, like #8 which is pretty accesible and probe both sides of the #8 wire looking for continuity. It should read 1, ie, no continuity.

Just some other things to check first.

Where are you located?

 

I never thought about the ecu not getting voltage. The injector relay is old but seems to be working, when I turn on the key I get voltage to the injector harness. I am located in Sarasota Florida. The positive wire that controls the ecu, would you know if its fused?

 

I have one PM me

 

If you live is Sarasota you should ask meet our local group, four of us should be in Sarasota tomorrow!

 

what was the last thing you fixed?

 

Not fused. Direct from little red wire on battery.

I'd jumper the injection relay, 30 to 87 to 87a (sometimes both are labled 87). Sometimes one circuit works, not the other.

Grounds for electronics need to be clean. Two sets of wires on passenger side cam cover, generally obscured by the piping and valve leading from the air pump.

The right most two plugs on the lower edge of CE panel are critical, too. Ensure each wire is seated.

Ignition switch can fail also, jiggle a bunch to clean contacts within.

So many things are known causes. Dirty 14 pin connector can bring them down, too, via corrosion.

Grounds need cleaning annually, at least biannually.


Now Tampa (local to you} and Merlin are in here, follow their logic and you will sort it out quickly!

 

Green wire?

 

Do you have spark ?

 

It was the afc relay not powering the ecu. Put a three way jumper car started and drove home. Thanks Landseer for the insight. The wiring diagram does not show two 87 plugs on it. Anyway, where is the best place to get one. Thanks to all for the help. Brian

 

Thats right, the diagram doesn't show it. Glad you have the diagrams, BTW. Most don't.

The three large capable, active suppliers of the majority of these parts are 928 International, 928sRus and 928 Specialists, you might want to shop them for all your parts needs on these. Very good, each with their own flair.

And John Speakes, who posted, is also a sponser and he specializes in the ECU rebuilds, MAF rebuilds for the later cars, etc, and has at least one USA-based distribution and testing point. Very reliable if/when you need that sort of thing.

Big suggestion, get with 928sRus at some point and buy the CD that he resells, assembled by an enthusiast, that includes the WSM, all year wiring diagrams, plus, and this is big, a treasure trove of model year and systems specific dealer service documentation. It costs less than 100 and is invaluable to me.

Good luck! Hook up with Tampa et. al.