3.4 cel

I recently purchased a 02 tacoma crew cab. I know the motor fairly well as I also owned a 97 extended cab before this. I have a check engine light that come on that I've never had before. Po128 is the code. Say my pickup is not warming up correctly in the amount of time it's running. Possibly thermostat. Question is, the pickup came from North Dakota where it was set up for the cold temps. Coolant in it is rated for -40 or more. Could this have something to do with my light coming on? Since thermostat is fairly inexpensive I am going to replace that and the coolant. Curious if anyone else has had this problem? Thanks for the help

 

-40 rated coolant has no bearing on your issue. Likely a bad thermostat or bad temp sensor.

 

You think front temp sensor? Behind timing cover?