What's a crankshafts censor? on 2002 Saturn SL1

Where is it located & is it hard to replace?

Asked by for the 2002 Saturn SL1
Under Intake manifold on firewall side. Hopefully you've had vehicle inspected by an ASE Certified Technician already. I'm sure it would be helpful is you had the replacement part on hand as well. Hard to replace? that depends on your mechanical abilities/tool arsenal too. Good Luck hope everything works out.