Car seemingly gets hotter while idling?

Question

I have a 1999 Ford Taurus coming up on 100,000 miles, and recently I've noticed that my temp gauge seems to go up after I get off the freeway to stop a red light, but while on the freeway or while just city driving it goes right back down to normal. I got an oil change recently for what that's worth, could it be a filter or something?

I'd like to know a bit about the problem before I take it in.

I'm planning on going on a 6 hour drive in about a week and I want to know if it's safe.

I know nothing about cars, so any help would be great.

Thanks

Answer 1

The car gets hotter due to less airflow over the radiator.  If it is in the normal range and the fan comes on then it is nothing to worry about.

Answer 2

Your radiator cooling fan probably is not working!  Most likely a fuse, relay, sending unit or possibly the fan itself!  Some cars have 2 fans, - one runs with "warm" engine (when over a certain "normal temp"---   The other will come on with a/c turned on (to aid cooling of radiator) If this is the case, sometimes the  system has a "bypass" that goes "around" the other electrical stuff and turns on the fans all the time compressor is running (hot or cold)!

Now what is happening is that after you reach 30-35 mph, the air pressure across front of car forces through enough air to cool off engine, --  And normally after it cools down a little.... fan (if working) will shut down -- till you slow down again!  So in an emergency if system is wired so fan runs with a/c turned on, - you can leave it on, with cooing fan on low, -- and if you don't want the cold, just unplug the  plug going to compressor clutch, -- this will keep engine cooled, and will turn off whenever you turn off ignition!  This may come in handy somewhere down the line-- to know just in case you have fan problems!

Answer 3

When your driving on the freeway your car has a very effective cooling method: the wind.

The front grill forces air over the the radiator section which is separated into many tiny fins to maximize surface contact and heat transfer.

So when the air passing leaves the car it takes away some of the heat from the engine. The faster you go the more air passing through the grill (generally) and can potentially cool the engine more of course at a certain point the engine will start producing more heat than the air can remove (if you redline it constantly).

When you pull up to the lights the heat that was generated while on the highway has only just transferred from the engine block to the coolant but now you have no wind to remove that heat. That is why cars are fitted with big radiator fans these days, they kick in when your stopped or slow so the engine doesn't overheat while. However these aren't as good at removing heat.

So you probably don't have any problem if its not going right into the red zone on the gauge. Maybe replace or top up your engine coolant and check your fan works, belts are tight etc. before you leave and carry a couple bottles of water if your really worried.

Answer 4

I would not worry about your issue unless if it overheats. What I would suggest is if the coolant hasn't been flushed for more than 2 years is do that. You might also want to think about replacing the radiator cap (especially if the gasket inside the cap looks worn or if the spring or inner part looks too rusted out).  

Answer 5

Sound to me like you need a trany service.  The pump inside of the transmission slows down as vehicle speed slows so any restrictions become more noticable when stopped (clogged trany filter and old fluid that doesn't transfer heat as well seem the most likely cause).  

Answer 6

Your fan isn't working. While moving, air passes thru the radiator and cools the water. When you stop the water gets hotter the longer you are stopped when the fan isn't running. If you set too long it can over heat and cause damage to the engine. If the fan is bad I would get one from a junk yard for half to a quarter of the cost of a new one. You could also have a blown fuse. Good luck.