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Here's my interpretation of the FI Green Book info...
"The 1-4-4 code is set because of a missing "load signal" (sampled twice each engine rev) from the FI ECU (pin 25) to the Ignition CU (pin 8). Across-the-car wiring and two connectors are involved, but the signal loss is more likely (IMO) due to a momentary loss of main 12V power to FI ECU pin 9.
Fuel relay terminal 87/1 supplies this main voltage to ECU-9, making that relay terminal connection suspect. That includes the female connection in the relay rack as well as the relay itself (PC board and male terminal).
I can't find it now, but believe I've read (re the 1-4-4) where that 87/1 female rack terminal had to be replaced due to corrosion or arcing, or a failing crimp connection.
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