New owner, and new poster.

I just purchased a mazda b3000 or ranger V6 3.0. On the drive home, i notice that the temp gauge would steadily go up to about 3/4 mark from the normal mark in a couple of seconds. It would sometimes stay there a bit, and then all of a sudden drop down to about the 1/4 mark in a few seconds, only to go back up again.

On the freeway, the fluctuations would still occur, yet less pronounced. I had to turn on the heater to make sure it would be okay.

In any case, engine has 80K miles on it, prev. owner never changed the thermostat.

Anyone have ideas? I'll be changing out the oil, coolant, thermostat, and teh drivebelt later today as part of my regular maintenance.

 

Welcome to Ford Truck Enthusiasts!

The sudden fluctuations in temperature could be a bad temp. sending unit or air pockets in the cooling system. My suggestion is that you should also replace the Temperature Sending Unit (has single wire coming off it) sensor while you are in there changing the T-Stat.

And I would also consider replacing the Engine Coolant Temperature (ECT) sensor (has 2 wires coming off it), as well, since it can also break down over time, just like the sending unit.

Drain a little coolant out of the system first to avoid a mess, and then make sure you refill it completely and bleed any air out.

HTH

 

Thanks for the feedback man.

I changed out the thermostat for a 180F unit and flushed teh coolant, and everything seems good to go. Is a 180F too low? I know some people liek it, and some think its' too low.

 

I don't think that I would run a 180. Only because it will prematurely kill your cats. It may give a SLIGHT increase in power and drivability but, I don't think it's worth it in the long run.

 

stepman. Thanks for the tip. I'll probally change out to the 195F thermostat that's standard. I just wanted to make sure my car wasn't going to overheat again. When i took out the old thermostat...it looked liek trash....actually the coolant looks like trash too

 

Yeah, i ran a 180 in my truck and didnt see anything except the temp gauge always ran cool, and my gas mileage went down a little.

 

Thanks Peter. May i ask what climate you were normally at? I'm in the bay area california, and with summer coming, in highly doubt the truck will actualy stay at 180F, but probally a tad higher.

 

I live in minnesota with cold winters and hot summers, i put the termostat in around august, and took it out in october, so i really didnt see it in the summer