System which removes excess heat from liquid cooled internal combustion engine. It also helps maintain the engine temperature at a consistent level. The cooling system encompasses the radiator, water pump, thermostat, hoses, heater core, overflow reservoir, and anti-freeze (or coolant).

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2
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0answers
35 views

2006 VW Jetta Diesel won't warm up

A couple of years ago the VW (2006 Jetta) quit warming up. No heat, no defrost, temperature gauge reads cold! I changed thermostat and tested both 'stats at the same time. Both opened right at 195 ...
4
votes
2answers
49 views

Replace Yamaha FZ6 radiator for two smaller ones

I bought the engine of a Yamaha FZ6. I want to use it to run a competition single seater car we are builiding in the university. The engine didn't bring the radiator with it. I would like to ...
8
votes
3answers
218 views

Car won't reach operating temperature

Here's a seemingly simple problem - I noticed that the temperature gauge of my mother's 2004 Opel Meriva 1.7CDTI won't ever climb above minimum. I checked the OBD readings to see if it was a defective ...
9
votes
1answer
69 views

Coolant Reservoir

Two questions, One, is there any reason why some coolant bottles are shaped in this way? Two, if this coolant bottle was placed on its side such as in the image below for example would coolant ...
8
votes
2answers
58 views

Ford Expedition Eddie Bauer 4.6 V8 2003 automatic rpm goes high

When driving, sometimes when I want stop the vehicle, I go to press the brakes, but that time engine rpm goes high, keeping brakes pressed hard, after 5 second engine becomes normal. It goes high when ...
3
votes
2answers
157 views

MK 1 citi sport temp gauge fault

I own a MK 1 Citi Golf Sport 1.6 Carb that has 523220 km. I recently flushed the cooling system and changed the coolant. After the flush the temperature showed above normal despite changing ...
11
votes
7answers
8k views

Can radiator cool down a car too much?

Recently they replaced my stock radiator with aftermarket one (at dealership, so I hope they knew what they were doing), and since then I feel that a car is not warming up enough. Even if I warm it ...
6
votes
2answers
23k views

Why does my car sometimes blow cold air while the heater is on?

This started about a week ago. I put the heat on and about after driving a couple of miles with the heat on it would randomly blow out cold air. Sometimes if I turned the heat off or switched it from ...
3
votes
3answers
3k views

Pros and cons of using straight antifreeze

I've heard from some people that they use straight antifreeze in their cooling systems and not 50/50. What are the pros and cons of doing that? E.g. does it reduce exposure to corrosion?
5
votes
1answer
72 views

What exactly is meant by “engine coolant”?

I know that engine coolant is a fluid in the engine used to dissipate heat spots and keep the engine cool in general as the moving parts generate heat. In this context, I would call the oil an "engine ...
3
votes
2answers
1k views

How does the heater core work?

How does the heater core work? What are the inputs to the system? What are the outputs of the system? What are some common ways that it can fail?
6
votes
3answers
878 views

Golf mk3 TDI has pressure in the cooling system

I have an interesting problem on my VW Golf MK3 TDI. Basically, sometimes the pressure cap on the coolant reservoir lets out some coolant. Here's what I know: It happens when the car is under ...
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vote
1answer
24 views

2000 Vw passat 1.8l oil is in radiator

I have a 2000 VW Passat GLS 1.8l and it has oil in the radiator reservoir. and my Oil light says oil compression low. i flushed the radiator and found oil in it again, (the radiator overflow) it ...
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votes
7answers
44k views

The mysterious overheating honda civic

This is a tale that goes back about a year when I found my very first car. I needed it to commute back and forth to school. When I bought the car it worked great, everything I could have wanted. ...
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vote
3answers
13k views

car over heating and white smoke coming out of the hood

I have a 98 Honda civic that I bought a few months ago. It has an after market fan that i have to turn on when I'm driving to keep it from over heating. In the winter time it wansnt a big deal to turn ...
5
votes
2answers
42 views

Water underneath floor carpet - Mazda Protégé 2002

I just bought a Mazda Protégé 2002 and a few weeks later I noticed a damp spot on the back passenger side floor. Very wet and soaked. Later I noticed the smell grew larger and the vapor on the glass ...
4
votes
1answer
111 views

How can I test my thermostat?

How can I tell whether a mechanical thermostat works as it should? Is there a test that can definitively tell me if a thermostat is good or bad?
1
vote
1answer
17 views

1978 Ford 302 is using a lot of water

My 1978 Ford 302 is using a lot of water. There is no oil in the water or no water in the oil and I cant find any leaks. What can I do?
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votes
8answers
25k views

My car's coolant temperature reaches almost 100 C / 212 F in a fast pace

Today, after a very hot day, I saw that my coolant was almost reaching 100C/212, I pulled over, stopped and took a look over the hood. The very little water that remained in the coolant tank was all ...
4
votes
1answer
134 views

Car is heating while Coolant Temp Sensor is normal

I bought a BMW 318i and the car heated twice so far while the coolant temperature sensor is normal. If we exclude the possibility that the sensor is malfunctioning, what problem would cause the ...
7
votes
2answers
10k views

Why would my engine temperature raise from normal to high and drop back down again?

I have a Nissan Micra (UK, 51-plate, 2001 model) that I have been using to drive to work on a daily basis - 10 miles each way a day on a variety of roads - streets, main roads, main roads in traffic, ...
9
votes
5answers
115k views

Oil in the radiator, but no coolant in the oil

The car is a '98 Buick Lesabre with the 3800 engine and about 170k miles. It appears as though some oil was in the radiator, but I haven't seen any signs of coolant in the oil. The water pump recently ...
2
votes
2answers
126 views

1996 mazda 626 leaking coolant

My mazda 626 was leaking coolant. I replaced the radiator for there is clearly a hole on it. It worked fine for about a month. Then I see some leakage again. And this time it is around the right side ...
5
votes
2answers
70 views

Why is antifreeze mixture not as stated?

To keep things short I poured 200ml of concentrated genuine ford super plus premium antifreeze (Ethylene glycol based) within a bowl. Then added 200ml of water to dilute the solution to a 50/50 ...
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vote
2answers
102 views

2005 Honda Civic - Oveheating [closed]

So my car has been overheating for over 1 year. It overheated during summer or when I went 80mph only. I recently saved up enough money to get the car fixed. I brought it to my mechanic and informed ...
4
votes
5answers
14k views

F-150, heater will blow hot, then cold

F-150, heater will blow hot, then cold and then heat gauge will rise to extreme high, will boil over then gauge will drop to normal. Just had it flushed and no change. After driving for about 10-15 ...
2
votes
2answers
66 views

Coolant disappears from coolant reservoir but no leak observed

I just replaced the water pump in my 2005 Ford Escape V6. I discovered that each time I fill the coolant reservoir with coolant and drive the car, by my next stop the coolant reservoir will be ...
2
votes
2answers
6k views

Bent radiator fins — how many is too many?

Hi I thought I fixed some previous overheating problems but I only helped them. My car was running fine when it was 95F or so over the weekend but now it's 110F(yes, hell, I know) outside and my cars ...
2
votes
0answers
94 views

E46 rough idle with coolant light on

The car is 2001 BMW 330i. I have changed ignition coil, spark and IAC. Last week, my car experienced rough idle. Then I changed the coolant temp sensor today. After adding coolant and bleeding, the ...
11
votes
4answers
136k views

Can I drive a car with only water and no coolant if it has a leak?

Recently, I was informed that a car I share ('02 Nissan Sentra) was close to overheating. I was told it gets close to the upper limit very quickly upon running the car. When I inspected the vehicle, I ...
7
votes
3answers
420 views

Blocked water flow in engine?

My dad has a 1993 Subaru Legacy L 2.2L (no turbo) with a perplexing cooling problem. It overheats, and there doesn't appear to be flow through the cooling system. The upper radiator hose is extremely ...
2
votes
1answer
44 views

Engine oil going into the coolant

My 2005 Saturn Relay got a hole in a water hose and suddenly overheated, so I shut it down immediately. Found the crank case empty and the coolant full of oil. Replaced the hose and put oil in it, ...
4
votes
1answer
40k views

Getting the best results sealing head gasket leak with Blue Devil

The 1998 Subaru Outback I've been having cooling system problems with turns out to have a combustion gas leak into the coolant. I suspected this but couldn't get a test to turn up anything; taking it ...
3
votes
2answers
98 views

1.6 Petrol engine overheats intermittently

I have a Vauxhall Vectra 1.6 (2007). The cooling system operated perfectly (a few kms after starting the engine the needle was pointing to optimum temperature without the slightest waver). 2 weeks ago ...
0
votes
1answer
78 views

Does using heat in the car SAVE gas?

Its well known that using heat in a car is almost free (see for example here). It is also known that using the heat can reduce the engine temperature which otherwise needs to rely on water cooling. ...
3
votes
1answer
5k views

Coolant spillover tank boiling but engine not overheating

After driving some time, is it normal that the plastic spillover coolant tank, usually attached to the fan housing, that takes boiling overflow, get so hot that you get bubbles boiling out of it even ...
2
votes
2answers
146 views

Mazda 626 with Unknown Coolant Leak

I'm looking at a 98 Mazda 626 2 liter with an unknown coolant leak from the area in the back of the engine. Seller says a mechanic that quickly looked it over said he thinks it's either the head or ...
5
votes
1answer
501 views

Should overflow tank be filled when replacing coolant?

I have recently fully rebuilt my engine, minus the block and pistons. All the gaskets were replaced, valves lapped, valve lashes tuned etc. I did it because I had an overheating problem and a head ...
3
votes
0answers
110 views

2002 Dodge Ram 1500 overheating

I have a 2002 Dodge Ram 1500 two wheel drive with a 4.7 liter engine. It's been overheating so I replaced the whole cooling system: I replaced the condenser cooling fan because its not coming on ...
2
votes
0answers
48 views

Changing Freeze Plugs on a Mazda 626

On a 98 Mazda 626 4 cylinder 2L engine where are the freeze plugs and how hard is it to replace them?
4
votes
2answers
82 views

Is it necessary to maintain antifreeze to water ratio?

I had my radiator cleaned and flushed yesterday. The mechanic who did the work advised that pure distilled water is better than using mixture of water and coolant. I checked the manual and it just ...
1
vote
2answers
1k views

Can you drive a 1999 Dodge Ram 1500 when the heater core is bad?

I am thinking of purchasing an older Dodge Ram; the listing on craigslist says that the vehicle is in good condition but the heater core is busted. I'm willing to go without heat/AC till I get around ...
3
votes
3answers
317 views

Do cowl hoods actually help with engine cooling?

I've read that cowl hoods used to be the method for air induction for older vehicles with carburetors and that the only purpose they serve for vehicles with fuel injection is for looks. However, I ...
3
votes
1answer
2k views

Flushing built up Rust and Mineral Deposits in Cooling System

The previous owner ran tap water in the cooling system for few years, and we have very heavy, mineral rich water locally. When I bought the car about six months ago, I drained the water, and put a ...
1
vote
1answer
30 views

How to test if heater core is causing cooling malfunction?

My 2007 V6 Tacoma is overheating, I have done just about any test imaginable, replaced the thermostat, water pump, did many other checks, incl. chemical test for gas residue in the coolant system etc. ...
3
votes
6answers
47k views

What can cause a vehicle to run hot, but not overheat?

Anyway, I have a Grand Am 2003 V6. It only has 80k miles. My car ran great when I got it(used), but at some point it began to have minor temperature problems. It would always run a little bit hotter ...
2
votes
3answers
1k views

How to test if head gaskets are blown?

Is there a definitive way to test whether head gaskets in most engines are blown, without actually reaching for the gaskets themselves (at which point you might as well go ahead and replace them) ...
4
votes
1answer
181 views

Flushing coolant after driving only with water in

If I drive my truck for 30 min with just water in my system, would it be equivalent to just flushing it stationary (the proper way to flush it)? IOW, if I just drive around with a clean water refill ...
3
votes
1answer
4k views

Can a blown head gasket cause overheating, without losing coolant?

My 2006 Subaru Outback overheated when my wife was driving. I got to the car that evening and its radiator was pretty low. I refilled it, and the car ran fine for a week. Then it overheated again. ...
5
votes
2answers
290 views

Ditch water in radiator

I lost a coolant hose going down the road and all my antifreeze was gone. I found a puddle along the road and filled my radiator back up after I fixed the hose. Will this cause electrolysis in my ...