Hi, to test the TPS, disconnect the white plug, use the centre as common and each of the other pins should have a simultaneous ascending and descending reading as the throtle is slowly opened and closed.

The readings should be smooth.

I dunno if a duff one will cause poor starting,
I doubt it will make a pot go off tho. Check the terminals / wires that run to the front coil, you may need to strip the rubber boot to get a good butchers at it.

Regards Phil