I am driving as my temperature goes from 210 to about 160 and goes and comes back up, could it be a bad sensor, i just replaced the thermostat and radiator about a 6 months ago what u think?

 

have u checked the coolant level? when u changed the radiator did u bleed the air out? what therostate did u use? 180 to 210 is about normal.

 

YEs i bleed the radiator and everything i used a 210 this hadnt happen until like two days ago. if it where missing coolant wouldnt the temperature go up not down

 

ive seen it go up and down because there wasnt enough coolant to get to the sensor all the time (really low) so it would go up when the fluid got to it and down when it went away and all there was was air. and ive seen it go up and down when the coolant was just low enough to effect the temp. when a little air got in there for a short time. could be the thermostat is sticking. what about the fans are they coming on? and at what temp?

 

When does it go up/down? It's fairly common for the temperature to rise when the car is idling, and then go down when you start moving. That's because there's way more air flow over the rad while you're moving.

 

It's actually when I am driving in the highway at like 70 to 80 mph

 

When you're at that speed, does it go UP or DOWN?

If the temp drops at that speed, it's completely normal.

If the temp goes UP at that speed, it's most likely either a clogged radiator or something blocking air flow past it. Check for leaves or dirt in the ductwork. If all those air passages are completely clear, and the rad is getting tons of airflow, then it's either a clogged rad or some other coolant-flow issue.

 

It drops1!!

 

then make sure the fans are comming on when they need to, also could be the radiator or something plugging the system.

 

So install a flush kit and do a flush and see what your coolant looks like. You may need a super flush, and depending on how bad it is, your thermostat may need cleaning/replacing. Any bad hoses? Leaks?