New Radiator

[sandman7445]

Replaced the radiator on my '07 Pathy a month or so ago. While I was at it I replaced the thermostat with a duralast and filled the new radiator with new coolant. Ever since the I've had erratic temp readings. Also the electric fan runs full blast when it the engine warms up. I used a funnel kit to get any air out and said problems remain. I'm considering putting the old thermostat back in (original) to see if that helps. What do you guys think?

[smj999smj]

You might have air trapped in the system. I'm not a big fan of aftermarket thermostats. Years ago when I worked for Nissan, many ran the coolant colder than the factory t-stat even though they were rated the same. Try jacking up the front end of the vehicle as high as you can, turn on both heaters to the highest heat setting and let the engine run. This usually helps purge any air out of the system. If you still have the erratic readings, I would install a Nissan t-stat.

[sandman7445]

Thanks a lot. I should've know better than to use an aftermarket piece.