Kiln_Red

I have bypassed the alarm already. The injectors aren't firing. AFC relay (XVI) doesn't get 12V to terminal 85. I'm seeing 10.5ish with my multimeter. I'm getting battery power at terminal 30 with the key off. No power at all to terminal 87. Terminal 85 and 87 were measured with the key in the RUN position. Grounds have been verified. Also, I just replaced the ignition switch with a new one this afternoon as kind of a shot in the dark. AFC relay can't be energized. Any thoughts from anyone with some L-jet knowledge?

I should add that this car had been sitting for some time as I had it disassembled for repainting. I have only driven around the shop where I work up until last week. I got finished with the paint work last Wednesday and then drove it home this last Friday. It's just started to act up within the last few days. I've been working through the wiring diagrams to try to better understand the flow path for the affected terminals on relay socket XVI (AFC Relay). I also found these tips put up by Rich Andrade here.

Kiln_Red

It sure does look pretty again, but none of that matters if it won't run.

Simon928

I'm not sure how this relates to the various power readings you described, but when I re-installed the engine in my '84 I was having the same no-start, no-injector-firing symptoms that you have. The fix for me was the infamous green wire that goes from the 14-pin connector at the hot post to the distributor. There must've been a break in the wire, because I replaced it with a new one and it fired right up.

Mrmerlin

How old is the green wire?
NOTE if the connector ends are tan or brown or crumbling and or the wire insulation is cracked,
then its time for a new wire they will usually last for about 25 years.

Make sure to remove and clean the 2 grounds on the right side cam tower,
one is under the EGR valve so its hard to spot.

Also these relays should be checked
XIV start relay
XVI Fuel injection
XVII Fuel pump
IX kick down
Fuse 13 fuel pump.

NOTE clean the the ground in the hatch floor area ,
usually near the right rear taillight on the wall or floor. will be a bundle of grounds ,
its behind the quarter liner

Kiln_Red

Thanks for weighing in, Stan. The green wire is néw. It doesn't have anything to do with energizing the AFC relay, anyway. I did clean both cam grounds again late last night. No change. However, I did make a breakthrough at plug X on the CE board. The connector wasn't completely seated because two of the wire leads were crushed too far to fit on to the corresponding terminals. Must have happened after my CE R&R last year. For this reason, I wasn't getting power to terminal 87 or 87a. I opened the leads, refit the connector, and again had 12V to X2, X3, X4, and X5 with the ignition on. The only bummer is I had to start it with a jumper because my brand new ignition switch isn't engaging the starter. BUT it is running again.

Mrmerlin

glad you found the issue ,
now any chance the starter relay is damaged.
Where did you get the IG switch? How old is it?

Kiln_Red

Nashville dealer actually had 2 in stock. I stopped by there as I was already in Nashville since that is where the nearest BASF distributor is to me and I wanted to use Glasurit for refinishing the 928 of course. No clue as to the age of the switch. I know Landseer has received a faulty new one before. I remember him commenting about that. They're definitely a weak point on our cars. I've had them fail in several different 928s and not always with the same symptoms.

Mrmerlin

I would suggest to put the old ignition switch back in see if you have any changes.
Maybe your new one is from the lot of failed IG switches