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Hi Todd,
I'm afraid you're chasing your tail with this CPR Blue wire "short". I'm assuming you are measuring resistance between the (unplugged) blue wire and ground. What you are missing is that EVERYTHING electrical connects to ground eventually. In my 1st post I told you how to _Isolate_ that blue wire circuit, but you mis-read it I guess. I said to unplug the AAV and the LAMBDA relay (not the FI relay). So you're still reading back thru the Lambda relay coil to ground. And the AAV & Lambda relay must BOTH be unplugged at the same time. The Lambda relay is out on the left fender rail near the Hi/lo headlight relay.
If you have Bentley, check it out on the '83 diagram, page 390-17, N2. Find the relay #159, that's the Lambda relay. Look at its coil terminal #86 and note the Blue wire and the off-page arrow pointing to 99/87b. Item 99 is the FI Relay, back on page 390-14. The off-page tie isn't shown there (we just have to live with it), but you can see a blue wire on 87b. It's effectively disconnected here until the relay picks, which will put +12v on 87 and 87b. But it _IS_ connected to the one you're probing at the CPR (and the AAV and the Lambda relay).
Follow that blue wire (dashed line) up to items 101 and 102, the CPR and AAV which are both tied to ground. So with your meter probing blue at the CPR, unplugging the AAV eliminated _that_ back-circuit to ground, BUT blue also goes (off-page) to the Lambda relay, and thru its coil to Ground, which is why your "short" is still there. Unplugging the FI relay means _nothing_ to that blue wire when the relay is "down", or open.
As for "shorting" the Bk ground wire to all the other FI relay plug wires, it's just an exercise in confusion. I'm pretty sure that all those relay wires (except the Red) can be traced _back_ to ground thru _some_ electrical component. You proved that with the Red/White wire. Your "short" from Bk to Rw vanished when you pulled the wires off the coil. Try it again and pull the coil wires 1 at a time. You should find that your "short" to Bk (ground) disappears only when the #15 wire (Bl? Br?) is unplugged. So you were reading back thru the low resistance primary winding. And I'll bet you can measure a "short" between the coil Blue wire and ground.
That's because your meter is putting voltage _backwards_ to all the places that get powered whenever that Blue wire does. Such as the hot side of fuses 11-12-13 for example. Then on to everything that gets fed from those fuses. Stuff like relay coils, light bulbs, etc., ALL of which are connected to the same _ground_ as your other meter probe. Ground is Ground.
At this point I can only refer you back to my first suggestions, which _assumed_ a possible fuel problem. And maybe you should try to refine and redefine your problem symptoms (i.e.
slackening speed") in a fresh posting. This one is now too top heavy, IMO.
Bruce
P.S. You said, "I don't know what the <, & +> or such things that you added to your response mean." Neither do I unless they were html tags for italics or something that didn't work.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.
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