Looks like your on the right track to me. I'd suggest you tap into each of the suspect wires and get a voltage reading from each while running. this will verify that you are getting the required signal from each. Fluke sells a nice wire piercing probe that clamps on and probes the insulated wire. This would be the best way to test this. If you can get a graphing multimeter, that would also be best.

As for the cam sensor you are right on. It's some type of hall effect sensor. take a look at the symbols on the diagram. The two on either side are "+" and "-" and the yellow/grey wire is signal.

After another look it seems the only one you will need to probe is the TPS. It appears to be that S2 will run 0 to 5 volts and S1 will run 5 to 0 volts. I'd make sure you get the right one of you need 5V at WOT.

The yellow/green "signal" wire on the MAS is definitely the correct wire. It appears that the yellow/white wire on the left is IAT.

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