Found this using google. This what Mr. Intense has to say,

Just visit any dealership (or anyone else with a Tech II or Snap-On scanner). Ask them to perform the Crankshaft Position Variation Learn procedure. If they aren't sure what that is, suggest to them that they follow the procedure for DTC 1336 - Crankshaft Position (CKP) System Variation Not Learned. It only takes a couple minutes.

Be sure to request 'DO NOT REFLASH the PCM'. If they misinterpret what you want and reflash the PCM instead of relearning it, all your new code will be lost forever.