OK, your barometer/MAP sort of sensor is just part of the MAF. Apparently your voltage is good according to the test mode. I'm fairly certain that the ECU sees the same thing as test mode does. Which leads me back to that you must have a grounding problem on the chassis somewhere.
Check the wires that come off your negative battery terminal. There is the big wire that goes to the engine, and then the 2 little wires that go to the chassis and into the wiring harness. I'm starting to think that your problem is the big wire. I have seen it before where an SVT ran on the ground strap wire I mentioned earlier until that finally melted through, and the engine stopped. All because the main ground wire was loose where it connects to the engine block. It can happen, that's why we first recommend checking battery terminals, then alternator output, then the other side of the battery terminal wires.
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Originally Posted by the user formerly known as ZX3_Chick
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