Car runs hot...

[alphatarget1]

My friend and I went mountain biking today and she drove us there in a 92 sentra with 170k km on it. She mentioned doing a road trip in a week and she wanted to drive the sentra. It's a car from the north, a lot of stuff is kinda rusty. I noticed that the temperature gauge runs on the high side compared to the other cars I have driven, so I told her it was a concern and she should get it looked at. Do you guys know what's the normal temperature? I was thinking I could use one of those infrared guns and point it at the radiator to see the temperature. Car has no A/C nor P/S and we were driving at around 50 mph, so even without the fans there should be enough air to cool the radiator.

Maybe it's just a faulty sensor and the car is actually not running hot, but who knows...

 

[obamanation]

First of all, how do you know the car is running hot? Is it because of the temperature gauge? If the temperature gauge says its running hot, then you obviously have a point of reference for which the temperature should be at, therefore your question about how hot it should run is pretty moot. If the car is running hot, ask if the coolant has ever been changed, my guess it hasn't. Drain the coolant, inspect it and replace with the manufacturer recommended coolant. If you find rust, algae or anything of the sort that doesn't belong, you've got yourself a mess on your hands which is going to mean a lot of work to not only get that gunk out of the engine but to also clean out and or replace the radiator.

 

[CraigRT]

It's also possible the thermostat is failing closed. That happened on my friends Mazda.

Nissans usually run somewhere closet to 1/2 on their coolant temp gauge.

What's your readout saying as far as that?

It's probably in the neighborhood of 180-190F rated thermostat, if you decide to investigate that.

 

[woodie1]

If the temperature gauge remains steady when she is driving in heavy stop-and-go traffic or sitting at a light I wouldn't worry about it. Most gauges are electrical so it could just be a voltage problem or it could have been like that since new.

 

[Raduque]

The temp gauge on my Altima sometimes freaks out and the needle bounces around because of the temp sensor(loose connection). Her problem is probably sensor related.

 

[radioouman]

The cooling system can have air trapped in it from a coolant change, low coolant, or a head gasket leak. That air causes the coolant to not flow. Many cars have a purge valve (or plug) at the top of the head to allow the air out.

I had a Dodge Dakota that had a bad radiator. It only leaked when the system was fully hot and pressurized. I believe a seal at the top of the radiator was leaking. It would cause the truck to overheat.... most likely because the coolant would boil since it wasn't under the correct pressure. There were no signs of a leak on the outside of the radiator, but a new one fixed the problem completely.

 

[Juddog]

Last time this happened to one of my cars, it ended up being that the radiator had a tiny leak in it and the coolant level was low.

 

[Bignate603]

It will be worth it to have somebody check it out if you don't want to or can't yourself.

I've had partial plugs of radiators before, sticking thermostats, and plenty of other things. Those are both pretty cheap fixes and you an actually do those yourself on most cars with a basic wrench set in one afternoon.