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IF the inducer fan runs, its good, you do not need a new one. In that case the pressure switch is most likely not closing, you can fit a jumper wire around it as a test *after the inducer fan starts... then if the the furnace fails to light, the problem is with the igniter or the printed circuit card.
If you can attach a close up, well focused, well lit photo of the wiring diagram glued inside of the blower door of the furnace I can mark it up with trouble shooting instructions.
Use the paper clip icon at the right end of the tool bar above or the '+attach files' link to the left of your send button for that.
We can go from there, if I miss you tonight I will pick up your response first thing in the morning.
Tell me about how old the furnace is as well please.