tps, iacv, airflow meter, engine temp sensor get their grounds from computer. at least as far as i can tell from the diagram. the engine temp sensors' ground from computer is connected to the tps's ground from computer. obviously, if computer is deciding when things should be grounded you dont want to just hook the wire to a fixed ground. can someone clarify this. it is late. the iacv aac do not ground by being connected to engine chasis, either. i think the ficd is connected to ground, though.
1991 240sx wiring diagram
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