Car Audio Central - Ultimate Car Audio Forum and Community

I was at the drive in with the car on so i could listen to the movie over my deck since my amps pull 900 rms of power and after like 20 - 30 minutes of being on i notice my car steaming and my temp gauge is at the top. So i shut it off let it cool down and put water in the coolant reservour. I drove home and it didnt over heat. What could have caused this?

I noticed my low coolant light come on whenever My car shifts into gear at high rpms but i was never really low on coolant and i didnt see coolant or water goin anywhere on the car when i had it runnin tonight.

Your water pump may have gone out or you just have a leaky hose or something. That's the two things that come to my mind.

Your water pump may have gone out or you just have a leaky hose or something. That's the two things that come to my mind.

The main reason is because the car was sitting. The only thing that can cool your car is the fan in that situation, in which you probably have an electric fan. When a car is sitting, you lack airflow across the radiator fins as well as air circulating throughout the engine compartment to cool the motor, exhaust manifolds, etc. It's also bad for hoses and wiring since so much heat is trapped there. You should never let a car sit and idle for more than a couple of minutes.

I'm guessing you probably had the a/c on as well. This taxes the cooling system further since the motor is under more of a load with the a/c on, as well as having to remove more heat from the condensor in addition to the radiator and transmission cooler.

The next point is that alternators stress to put out a reasonable amount of charging power at idle, and the lack of charge causes an electric fan to lose power and circulate even less air than it normally would.

You lost coolant when it was overheating. Obviously with steam that was the case, and if it got that hot it probably boiled right out of the reservoir. That isn't saying that you didn't lose some before then, but obviously you lost more tonight.

Couple of pointers, though. Don't run a lot of antifreeze in the summer. The only reason they recommend a 50/50 mixture of antifreeze and water is because of the corrosion protection that antifreeze has.

Water dissipates 2.5x the heat that antifreeze does. You want to run more water in the summer, particularly if you live in a hot climate. I usually do 30% antifreeze in the summer, and of course I add rust inhibitor to prevent corrosion. With particularly troublesome vehicles (say performance cars, trucks that are used with big loads) I have used straight water, rust inhibitor, and water wetter. Keeps things much cooler. You'll just have to make sure you go back to a winter blend when the time comes so the coolant doesn't freeze.

Electric fans are generally crap when talking about what comes from the manufacturer. They usually do just barely enough to get the job done if that, and the water temperature gauge is calibrated to have a pretty wide range in the "normal" region just so you don't get freaked out every time you're sitting at a stoplight. If you're unfortunate enough to own a FWD car, you have no other choice. Some manufacturers used hydraulic fans in the past (my Camry had one), but they really aren't much if any better. Nothing beats a clutch fan and a good shroud design

Aluminum radiators are nice as well since they can use bigger core tubes and dissipate much more heat.

Hopefully you didnt get it too hot and blow a headgasket or crack a head...

Thermostat stuck closed or the fan not kicking on is most likely the problem...

MobileAudio219 wrote:Hopefully you didnt get it too hot and blow a headgasket or crack a head...
Thermostat stuck closed or the fan not kicking on is most likely the problem...

Im thinkin i didnt blow a head gasket or crack a head or anything because the only place i found cooland was by the coolant tank and near the water pump, but if it was the waterpump it should have flung water or coolant when it was running.


I had no idea you shouldnt sit at idle. I thought it was perfectly fine to do that.

It's really not good to let your car run at idle for too long. Most owners manuals say to avoid doing this for long periods of time.

Like Jonathan said, the car just isn't getting the cooling it needs and your working your cooling system more.

So is it possible that it just overheated from sitting at idle, cause it was fine afterwards? Cause i have no idea what could have caused it since no water was flung from the water pump and there wasnt coolant all over the engine or anything. Unless the thermostat stuck and it like flowed out the overflow or somthin.

If the thermostat was stuck shut then the car would be overheating constantly. Just make sure to run the car and check for any leaks.

A car is pretty prone to overheating when sitting for that long just due to the amount of heat built up in the engine. Unless your car has a VERY good cooling system from the factory, but it's still not desirable to sit and idle that long because of the radiant heat you're putting on the wiring and hoses. It's also not as desirable from the standpoint of the engine because you're running a richer mixture to keep the car running at idle, and if you run that for too long you can end up potentially fouling spark plugs, leaving buildup on your valvetrain and cylinder heads, amongst other things.