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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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. ...
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1answer
53 views

Thermocouple vs Thermostat

Why don't modern engines use a thermocouple (electronic temperature sensor) instead of a (wax element) thermostat?
4
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1answer
45 views

Waterbottle cap still poping off

I have a 2008 Ford Fiesta 1.6i. The car heats up and builds pressure in the water bottle that causes the cap to pop open and boiling water to come out. I have taken it to Rord where they have done ...
4
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2answers
95 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 ...
4
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2answers
541 views

Bad dashboard coolant temp sensor?

In addition to the coolant temp sensor hooked up to the ECU, I have a second, single wire coolant temp sensor which is hooked up to the dashboard display. When the coolant temp is around 85C, right ...
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1answer
11k views

Engine's Normal Operating Temperature

I read in the Motor Oil University article on Bob the Oil Guy's websites that: The automotive designers usually call for their engines to run at 212°F ( 100°C ) oil and water temperature with an ...
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5answers
16k 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 ...
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1answer
147 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 ...
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3answers
4k views

Replaced water pump two days ago…today antifreeze filling up parking space

I have a 1998 Jeep Wrangler. A few days ago, I noticed the engine temp getting higher than usual. I'd checked fluids about a week prior. When I got home and checked fluids, the coolant reservoir was ...
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2answers
1k views

OVERHEATING 07 grand prix

My car has been overheating bad I took it to auto zone and hooked it up to the check engine thing and they said it was getting to 207 withing 10 secounds. It get hot fast and my heat doesnt work ...
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0answers
31 views

2005 Pontiac Grand Prix overheating

I have recently bought a 2005 Grand Prix V6 non supercharged. It overheats at idle and in park. I have had my head gasket and head resurfaced at Pepboys and replaced my radiator with a larger 1 inch ...
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0answers
114 views

Radiator has a leak and the upper hose is clogged, car does not overheat. White smoke from upper hose

My car is a 2003 Buick Century and it has been leaking for the past few months (puddles of coolant under the car). Now the car begins to have white smoke coming from the engine and it has a sweet ...
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0answers
68 views

Honda Civic 2002 Coolant sprinkles back from Rad cap

I am having issues with this car, so I am reaching out to masses out there who could share some of their wisdom to help me understand the actual issue with this car. It has 262K miles on it. Issue ...
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0answers
59 views

2006 VW Jetta Diesel won't warm up [closed]

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 °...
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3answers
184 views

Should I get a second opinion from a different mechanic?

Previous question for context TL;DR: My 2001 Pontiac Grand Am SE had a flashing check engine light and I found oil in the coolant. A family member took the car to a mechanic this week. He checked ...
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2answers
2k 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?
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5answers
53k views

Cooling fans not running

Update This question seems to be attracting a lot of views, so I guess a lot of people are having the same problem. Just to be clear, the problem with MY fans specifically seemed to be caused by my ...
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3answers
882 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 ...
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2answers
161 views

Effects of anti-freeze concentration on engine temperature

I am curious as to how useful the engine temperature sensor actually is. It tells you the coolants temperature obviously, but I have read that the engine actually operates hotter than the coolant. For ...
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2answers
501 views

Should I try radweld on this pipe or just replace it? Mk3 VW Golf

I have a leaking pipe in the cooling system of my Mk Golf. It leaks about a litre in 5 miles. I'm not sure if it's worth trying Radweld with this rate of flow or if I should just try to find a ...
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3answers
10k views

Are there any disadvantages to using a “Radiator Stop Leak” product?

I have had a slow leak form the coolant system for a few months, if I drive the car every day I have to top up every few weeks. The car has 200K on the clock and is a VW Passat TDI, I only drive ...
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1answer
30 views

Only one radiator fan running

Today while adding coolant to my car, I noticed that once the car reached running temperature only the fan on the passenger side had turned on. I checked the connection and that was fine, the fuses ...
3
votes
1answer
221 views

Coolant pressure issue

I am in need of some assistance. I am having a coolant pressure on my 1.8 16v clio. (Renault), coolant, cooling-system, overheating (car maintenance) In that when left to idle and engine gets up to ...
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3answers
7k 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?
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7answers
63k 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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3answers
1k views

Coolant still in expansion tank after draining from engine and radiator — BMW E46 (2003 330i)

I attempted to do a cooling system flush today (along with replacement of radiator hoses, water pump and thermostat). After removing the blue drain plug (my car only had one, apparently some cars ...
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1answer
70 views

Over heating of my 05 Honda Civic

I first purchased my Civic in Jan of 2015. My first car had terrible over heating problems so I decided to get rid of it for my civic. Turns out, my Civic has the SAME problem. I decided to take it ...
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2answers
46 views

My 2004 PT Cruiser is overheating

I have tried everything got a new radiator, thermostat, put blocked seal permanent head gasket fix. So I started my car and let it run for 15 minutes, after that I see no antifreeze in the reservoir.....
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1answer
35 views

Temperature gauge between half and 3 quarters?

I have a '98 Oldsmobile Intrigue and after about 20 minutes of driving the temperature gauge is between one half and 3 quarters. I was wondering if is this a problem? The coolant is at the right level,...
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votes
3answers
914 views

Oil in my radiator fluid tank?

I have a 97 Ford F350 with the 7.3l powerstroke diesel engine. There's oil where my radiator fluid should be. Do I have a blown head gasket?
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3answers
9k views

What is the Magic ON temperature for Electric Fans?

I want to wire up my old truck to turn an electric fan ON to keep the radiator cool. The ECM has an engine coolant temperature sensor mounted in the engine that alters the resistance to determine ...
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votes
4answers
10k views

Cooling fans constantly run

This past summer I inherited a 95 Pontiac Grand am that while looking under the hood, I noticed someone had removed the air conditioning unit. I drove it throughout the summer and wasn't until the ...
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votes
2answers
160 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 ...
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1answer
7k 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 ...
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1answer
2k views

Should I remove the thermostat when doing a cooling system flush?

I am going to do a cooling system flush and after some reading and watching some youtube videos I noticed that people take different approaches. So I have the following questions: I understand that ...
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2answers
240 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 everything....
3
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0answers
168 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 ...
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votes
4answers
867 views

engine has too much cooling especially when driving hard

I'm trying to figure out why my engine temp is always very low. I do know for a fact that my gauges work. My car is a 4-afe toyota with a stock radiator and a modified fan. I also installed 2 ...
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4answers
1k views

Clear water in coolant reservoir

Over the weekend I took my 2000 Toyota 4Runner to a local shop to get the oil changed. While there they told me I needed to flush the coolant, pulling clear water out of the coolant reservoir. They ...
2
votes
3answers
23k 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 ...
2
votes
2answers
9k views

How to diagnose excessive coolant consumption?

Whats the best way to determine the source of coolant consumption? How should one differentiate between say a leaking radiator, leaking waterpump, leaking hoses, a blown head gasket, or crack in the ...
2
votes
2answers
579 views

How to know if a radiator is getting sufficient airflow

I have recently purchased a dune buggy as displayed in the photo below. Note the position of the radiator located above the seats. What I am wanting to do is install some clear perspex in the window ...
2
votes
2answers
141 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
1answer
58 views

No fluid under thermal sensor | '89 Jeep Cherokee reserve cooling system won't drain? | Car dies while running? & Car dies without running?

!importantclosed-cooling-systemcherokee-89laredo6-cylender4-liternon-startstalling I'm wondering if the vacuum went bad, or if it could be anything else? !PULL THE METAL LEVER UNDER THE VACUUM WHILE ...
2
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1answer
55 views

No water flow in the radiator - 99 Cadillac STS

What's wrong when water doesn't flow from your radiator. I already put a water pump and a thermostat on putits still running hot. What could be the problem?
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1answer
47 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, ...
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1answer
325 views

Changed thermostat but now constant leak around thermostat housing

I went to flush my cooling system and change the thermostat on my Mk1 Golf. All went fine until I put the new coolant in. There is a pretty steady leak from the thermostat housing. I've tightened ...
2
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1answer
3k views

What is Honda Coolant?

My 2000 Honda Civic 1.6 Aerodeck is getting a little low on coolant, and so needs a top-up. The question is - what do I put in? The manual rather unhelpfully says "use Honda coolant", but doesn't ...
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2answers
7k 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
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1answer
2k views

Diagnosing overheating on 92 civic

I have a 1992 Civic that's been overheating, first only at speeds above 65 mph and only after an hour or so of driving, but it's getting progressively worse. It's drivable if I coast with the clutch ...