so my stock plastic radiator had a leak. so i got a full size mishimoto aluminum radiator, which by the way is not a direct drop in. you have to trim off a couple of unnecessary mounting points that you will not use. Now that it is in i am running extremely cold. i can drive for about 1/2 an hour and temp is about 1/2 way to normal operating temp. That is also on a hot day. what should i do?

 

this is sort of common although i upgraded to a similar radiator and I didn't have this problem and its fairly cold where i live. you could put some cardboard in front of your radiator to block some air flow, truckers use this trick alot.
you'll have to determine what size is best.

Are you missing your thermostat? maybe the previous owner removed it.

 

thought of that. also thought of unpluging the fan. wasnt sure that it was a good idea tho. not sure about the thermostat tho. need to check it.

 

dont unplug your fan, you will need it if temp goes too high, and it doesnt turn till normal operating temp

 

try checking the resitance on the TCS temperature control sensor.