Hi!
My check engine light came on right after I got my alternator changed at the garage. I got the code p1336 which is the Crankshaft Fluctuation Sensor. Is this something that needs to be fixed right away? Is it going to cost me a fortune? Please help... I'm a poor student :)

Juneau Alaska?
If so Hello Fellow Alaskan!

Before doing anything else, try resetting the ECM and see if the CEL stays off. Pull the BACKUP Fuse in the under-hood fuse box for 10 seconds or disconnect the negative battery cable for 10 seconds. Record any radio codes first.

So I did what you said. No other codes came up besides the P1336, and the light is gone... Am I in the Clear?

If Code P1336 is still being thrown, it needs to be fixed; otherwise, it is okay.