EDIT comment at bottom...

This thread seems to be going down the rabbit hole. Very little relates to the original post that said, "Mechanic said there was no spark at spark plug 1. I have not confirmed this." Confirmation would be best, but lacking it, I would stick to the "no spark" diagnosis.

That means that all the fuel-related comments about the FI ECUs, Fuel relay, fuse 6 (on a 1990), etc. have no bearing on the problem.

You might confirm that "Checked terminal 6, per Bentley 280.11.3, no power". But as Yama said, the fact that you can check codes at OBD socket 6 is a good indication of ignition switch voltage getting to the CU. I believe that "No voltage at ICU pin 6" would be a brickboard "first".

No Spark could be as simple as a broken or stripped timing belt—especially when you aren't sure if it was tensioned (or retensioned?) properly after replacement. [How many miles on it?] Has anyone watched to see of the camshaft (or distributor rotor) turns while the engine is being cranked? The teeth can strip down at the crank pulley, leaving the belt looking OK at the top, but unable to move the cams or rotor.

I would not be too concerned about timing being off either. While it could cause a no-start, there would still be a spark—just at the wrong "time").

And, unless I missed it, nobody has yet mentioned the Power Stage (item G in Bentley 280-10 fig. 19). That's what actually "triggers" the coil, under CU control. They are known to go bad with age. At least try reseating the connector. The one clue to a failing PS is wet plugs but no spark. All other ignition problems will, by design, prevent Fuel operation.

Sorry this is so choppy, but I wanted to summarize things to date.

EDIT: My point (not well made it seems) is that the spark question was mentioned in the original post. So until a good spark is verified, it's a waste of time to chase fuel issues. The complete FI system is dead without timing pulses from the ICU. We need to know whether there is, or is not, a working ignition system. And if it really is OK, that both t-belt driven shafts are in time.

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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.