OT-Saturn SL1 Won't Warm Up, Help Please! Options

[SteveL]

Mom drives a 1997 Saturn SL1.
Last winter it had great heat. Once Warned up, temp guage was solid at 1/2.
Over the summer, the radiator died. Replaced with brand new. I also replaced the thermostat with a standard replacement.
Now, the temp guage only barely gets to 3/8, and it isn't hot enough to make good heat here in MN.

Help Please?

[angerosa]

The mixture could cause that much of a difference becasue it's not that much of a difference.

Isn't the temp guage reading the block temp?

If your heat inside the car is not blowing enough hot to keep the inside of the car toasty then I'd assume:
You are not getting coolant in the block and head to flow through the heater core.
and
You are probably OK in the winter becasue it's cold enough to keep your car from overheating.
and
If not fixed you will probably have issues in the summer.
and
IM experience if you have air in your cooling system your car get's hotter but that was on a car with the temp sending unit in the head.

Check the coolant level when the car is cold. If there's not enough fluid in there it will be obvious.

Remember coolant keeps the fluid in your system from freezing when the car is not being used in the winter. It's the water that actually cools the engine down. So a previous mixture that had too much coolant in it could have made the temperature guage register 1/8 higher. This might happen when you have a bad radiator and you keep adding coolant becasue it's leaking out.

Although it's unlikely you have a bad t-stat, if none of the other easy remedies check out, it might be the case. Also to throw something else into the mix, the climate control switch may not be redirecting air to flow through the heater core any more. Check that out. It's easier than a t-stat.