[peterjon1]

I once had the same issue, replaced the solid state relay, and all was well. Access the relay from underneath.
Mine would maintain normal temps while moving, but temps would rise quickly idling.

 

[peterjon1]

You don't have to mount it back in the same spot, just anywhere the connector will reach. It should be attached to a flat metal area, since the relay needs to use the mounting point as a a heat sink.I think there is a heat transfer paste or grease you can put on it to aid that. IIRC, I attached mine to the radiator support.
I think mine was about $35 from Rockauto.

 

[peterjon1]

P1491 is for the radiator fan relay circuit, so since that is where your problem has been, try a battery or IOD disconnect and see if it returns.
From Here: http://www.allpar.com/fix/computer-codes.html

 

[peterjon1]

:thumbsup: