car getting hot at idle

[ino uno soweno]

The other guy who I thought might know, said thermostat, radiator, so no more clues there, ??. like I said I don’t know, and can only suggest we go back and check the info,
While thinking about this it occurs to me that when I start my cars, most of them kick straight into full choke, to warm up, then the choke shuts off, and idles back to around 700rpm,
So does that happen to you, does your automatic choke kick in, then return to idle, and then as you say heats up while idling after the choke cycle , ??
It also occurs to me that overheating while idling could be caused by the idle being too slow and not have enough circulation to remain cool. (Just thinking out loud), and wondering if you can tell what rpm your car idles at, and can you say the rev counter is accurate,
One scenario could be the rev counter is faulty, giving false reading, I do not know but think perhaps I might not notice the engine of 01 Honda idling low, no offence meant, I am just trying to help,

 

[BUTCH1]

The other guy who I thought might know, said thermostat, radiator, so no more clues there, ??. like I said I don’t know, and can only suggest we go back and check the info,
While thinking about this it occurs to me that when I start my cars, most of them kick straight into full choke, to warm up, then the choke shuts off, and idles back to around 700rpm,
So does that happen to you, does your automatic choke kick in, then return to idle, and then as you say heats up while idling after the choke cycle , ??
It also occurs to me that overheating while idling could be caused by the idle being too slow and not have enough circulation to remain cool. (Just thinking out loud), and wondering if you can tell what rpm your car idles at, and can you say the rev counter is accurate,
One scenario could be the rev counter is faulty, giving false reading, I do not know but think perhaps I might not notice the engine of 01 Honda idling low, no offence meant, I am just trying to help,

You must be new to cars, there is no "choke" anymore, all cars since the mid 80's are fuel-injected, the car's computer or "PCM" as it's commonly called will feed a cold engine more fuel when it's first started and cold, once it warms up it goes in "closed loop" mode where the engine get an amount of fuel depending on several factors, this is accomplished by keeping the injectors open for longer intervals, allowing for more fuel to be delivered to the cylinder.

 

[OGOC]

The needle goes to red

In case anyone reading might not know, when your temp needle goes to red, that's really bad. If there isn't major engine damage yet, continually going into the red will do it. Blow head gasket, warp the head, fun stuff like that.

Speaking of blown head gaskets, if you added coolant for no other known reason such as simply an external leak at a hose or thermostat gasket, I'd keep that possibility in mind. You can get a pretty good idea of it yourself by doing a compression test. Might even be able to borrow a tester free from Autozone or similar, and if it's a 4-cylinder, the plugs are all on top, so easy.

I'd probably start by eliminating the thermostat possibility completely by taking the thermostat out. The car may run "heavy" and get worse mpg due to possibly having a hard time warming up enough to go into closed-loop mode, but taking the thermostat out is still the easiest way to fix a stuck thermostat. ...or when you take it out, boil it in water and see if it opens at the right temp, and if it works put it back in. That works too.

 

[pcgeek11]

Air pocket trapped in the engine block is the most common cause of this.

 

[ino uno soweno]

Hope so,

What is the best way of checking, and removing a air pocket,, please,

 

[JCH13]

Hope so,

What is the best way of checking, and removing a air pocket,, please,

A coolant bleed. Your FSM should have a procedure for this.

If your coolant hasn't been changed/flushed in a few years go to a garage and have it flushed unless you're comfortable doing it yourself.

 

[ino uno soweno]

all good advice thanks,

 

[SAWYER]

I have had this car three years or so and never changed the coolant

 

[Zenmervolt]

I have had this car three years or so and never changed the coolant

While I generally think that changing the coolant every 2 years is a good idea, most new cars don't strictly require that (some claim a mileage number, others used to claim "lifetime" coolant).

Regardless, you should not lose any coolant between changes. If you had to add coolant, something is wrong.

Run a compression check for each cylinder. If one is low, you might have a slight head gasket leak that's allowing combustion gasses into the cooling jacket without letting coolant into the cylinders.

ZV

 

[JCH13]

In a very rare circumstance I've seen an engine with a crack in the cylinder wall pass a compression test (and it would have passed a leak-down test given the location of the crack) but would displace coolant.

I would suggest getting a kit to check for combustion gases in the coolant in addition to what ZV suggested.

 

[ino uno soweno]

[FONT=&quot]

There is absolutely no possible way that the Idle Air Control Valve (the term used by Honda for that part; any decent Honda mechanic should call it that and not an "electrical idle control module") could cause overheating.

ZV

[/FONT]
[FONT=&quot] If "no way possible", could cause overheating, with all respect, that sounds like you know what you are talking about, so can you please tell me for my own curiosity,” could a malfunctioning computer cause the IACV to cause overheating”, ??. if so any thoughts you might have on how a computer behave, ??. do you have any top secrets, ?? would be apprieciated,
[/FONT]
[FONT=&quot]
[/FONT]
[FONT=&quot] As I said I do not know and would be grateful for any tips,

Also you say, Any decent Honda mechanic should call it Idle Air Control Valve, suggests that any Honda Mechanic that can’t speak English could never be a decent Honda Mechanic,???. [/FONT]
[FONT=&quot]The Honda mechanic who I refer to, speaks very very very little English, and the “electrical idle control mod, was my translation, electric = computer, Idle = idle, control = control, it was close, everyone knows what we are talking about, [/FONT]
[FONT=&quot]Have a nice day,
[/FONT]

 

[ino uno soweno]

01 Civic

when sitting idle it will get hot however if I rev the engine while idle is will cool down. It also gets back to normal when driving. Thermostat? Water pump?

Please do not think for one second that I am being a smart ass, or anything like that,


I am just not sure of how mechanical you are, and I just hoping you are not as lazy as me, haha, joke,
And if you are aware of some simple checks you could do to gain more clues for a cheap solution for you, to that end, I have been ringing some people here, I know that they thrive on this sort of stuff,
So, have you? or you can try this, the car should be already driven and warmed up, then left cool for 15 mins, so the radiator water is only “ warm “, and not “ hot “, ( think 3rd degree blister burns to chest ,and or belly, and or groin, ) so I suggest once the engine “ Idles “ smoothly, hand brake on , out of gear, and open bonnet, remove the radiator cap using a big thick cloth cover, ,


(please do not rev the engine while the cap is off, coolant will just spew out, also when you remove the R/C there may be a small but lively pressure release, and a dribble of coolant, then nothing, that is ok, if the coolant starts and continues to spew coolant, lock the cap back on quick, )


With the cap off, You should see the coolant moving inside the radiator, you might need to just top up the radiator with a 1/8 cup of coolant or water, at which point looking from a distance for “ bubbles “ breaking the surface, either a small slow steady flow of bubbles, or intermittent belches of bubbles, or any extra bubbles at all,


After a few minutes, and If you cannot see any bubbles coming from deep in the radiator, we may assume there still may be the chance of a blown or leaking head gasket between cylinders, which does not leak into the cooling system, in which case could or most probably result in a rough idle, ??. At least different idle than usual,


Next suggestion, I got off a friend is the overheating could be caused by “dirty injectors”, and suggest a $12 or so dollar bottle of injector cleaner, and 2 tanks of premium fuel, could be a cheap easy fix IF that is the problem, %95 works, ( perhaps think about the last time you had your injectors cleaned, and or the last time you used injector cleaner) , restricted injector nozzles can cause the mixture to run lean, and quickly heat up everything,
2 easy checks,
That is it for now, have a good day,

 

[LTC8K6]

I can't think of any way dirty injectors would cause overheating.

Also, dirty injectors would cause all sorts of drive-ability problems which anyone would notice.

 

[ino uno soweno]

You must be new to cars, there is no "choke" anymore, all cars since the mid 80's are fuel-injected, the car's computer or "PCM" as it's commonly called .

IN reply to your post,
You must be new to cars,
I have been on the road driving “cars” since 1967, that is 46 years, And I still remember most of my FIRST drive, could you PLEASE explain what you meant by “You must be new to cars”,
the car's computer or "PCM" as it's commonly called
[FONT=&quot](PCM)[/FONT][FONT=&quot],[/FONT] [FONT=&quot] power-train control module (PCM),[/FONT]
[FONT=&quot] Also known as engine control module (ECM) or engine control unit (ECU),[/FONT]
[FONT=&quot]I thought you said, “ all cars, “ [/FONT]
[FONT=&quot]For anyone who does not know, and or who does not want to learn the difference ECM<PCM<ECU< my suggestion is just call it “ a or my car computer “,[/FONT]
“there is no "choke" anymore”,
Water temperature correction: Allows for additional fuel to be added when the engine is cold (choke) or dangerously hot.
In case you missed it, the word (CHOKE,) is used in reference to WTC as above and in most inter-net sites I searched.
miss-information. , b/s……… Big Smile (Internet chat)………….[FONT=&quot][/FONT]
http://encyclopedia.thefreedictionary.com/Idle+speed

 

[LTC8K6]

IN reply to your post,
You must be new to cars,
I have been on the road driving &#8220;cars&#8221; since 1967, that is 46 years, And I still remember most of my FIRST drive, could you PLEASE explain what you meant by &#8220;You must be new to cars&#8221;,
the car's computer or "PCM" as it's commonly called
[FONT=&quot](PCM)[/FONT][FONT=&quot],[/FONT] [FONT=&quot] power-train control module (PCM),[/FONT]
[FONT=&quot] Also known as engine control module (ECM) or engine control unit (ECU),[/FONT]
[FONT=&quot]I thought you said, &#8220; all cars, &#8220; [/FONT]
[FONT=&quot]For anyone who does not know, and or who does not want to learn the difference ECM<PCM<ECU< my suggestion is just call it &#8220; a or my car computer &#8220;,[/FONT]
&#8220;there is no "choke" anymore&#8221;,
Water temperature correction: Allows for additional fuel to be added when the engine is cold (choke) or dangerously hot.
In case you missed it, the word (CHOKE,) is used in reference to WTC as above and in most inter-net sites I searched.
miss-information. , b/s&#8230;&#8230;&#8230; Big Smile (Internet chat)&#8230;&#8230;&#8230;&#8230;.[FONT=&quot][/FONT]
http://encyclopedia.thefreedictionary.com/Idle+speed

Yes, I guess.

But there still isn't a choke on modern passenger cars anymore, except in very backward countries with very far behind car factories and non existent smog regulations.

Or on a pretty old car.

There is one on my lawn mower, though.

Wiki:

Carburetors were the usual method of fuel delivery for most US-made gasoline-fueled engines up until the late 1980s, when fuel injection became the preferred method.[7] In the U.S. market, the last carbureted cars were:

1990 (General public) : Oldsmobile Custom Cruiser, Buick Estate Wagon, Cadillac Brougham, Honda Prelude (Base Model), Subaru Justy
1991 (Police) : Ford Crown Victoria Police Interceptor with the 5.8 L (351 cu in) engine.
1991 (SUV) : Jeep Grand Wagoneer with the AMC 360 engine.
1993 Mazda B2200 (Light Truck)
1994 (Light truck) : Isuzu[8]

In Australia, some cars continued to use carburetors well into the 1990s; these included the Honda Civic (1993), the Ford Laser (1994), the Mazda 323 and Mitsubishi Magna sedans (1996), the Daihatsu Charade (1997), and the Suzuki Swift (1999). Low-cost commercial vans and 4WDs in Australia continued with carburetors even into the 2000s, the last being the Mitsubishi Express van in 2003.[citation needed] Elsewhere, certain Lada cars used carburetors until 2006. Many motorcycles still use carburetors for simplicity's sake, since a carburetor does not require an electrical system to function. Carburetors are also still found in small engines and in older or specialized automobiles, such as those designed for stock car racing, though NASCAR's 2011 season was the last one with carbureted engines; electronic fuel injection was used beginning with the 2012 race season.[9]

 

[Zenmervolt]

So, have you? or you can try this, the car should be already driven and warmed up, then left cool for 15 mins, so the radiator water is only “ warm “, and not “ hot “, ( think 3rd degree blister burns to chest ,and or belly, and or groin, ) so I suggest once the engine “ Idles “ smoothly, hand brake on , out of gear, and open bonnet, remove the radiator cap using a big thick cloth cover, ,

OP, DO NOT TRY THIS! THIS IS EXTREMELY DANGEROUS!

15 minutes is NOT enough time for the coolant to appreciably drop in temperature and you should NEVER open a radiator cap unless the system is COLD.

If you need to have the cap off with the engine running, you should let the car sit without running for long enough that the radiator itself is cool to the touch. Then, remove the cap first and start the engine. The engine will come up to operating temperature in 5-10 minutes and the thermostat will open, allowing coolant to flow through the radiator, when you would (potentially) start seeing bubbles.

NEVER remove the radiator cap while the engine is running and NEVER remove the cap unless it is cool to the touch.

As for how I know the IACV could not cause overheating, I know it because I understand how an engine works. The IACV simply compensates for additional parasitic drag on the engine by allowing slightly more or less air to bypass the throttle plate and thereby maintain a constant idle RPM even when there are additional loads on the engine (automatic in gear vs neutral, A/C compressor cycling, variations in atmospheric pressure or humidity, etc.). None of these in any way affect whether the engine overheats or not. No matter what the ECU tells the IACV to do it is not possible for the IACV to cause overheating because nothing the IACV controls can cause overheating.

The OP's situation is this:

1) He has recently added coolant
2) If he revs the engine slightly, the temperature goes down
3) The fans are coming on as expected

This indicates that he is losing coolant somewhere and that the system is able to generate enough flow for adequate cooling with higher RPM and that the problem is not insufficient airflow over the radiator (since the fans do come on).

The #1 most common cause with these symptoms is an air pocket in the system caused by combustion gasses somehow entering the cooling jacket. Alternately, the water pump is starting to fail and is not moving sufficient coolant at idle.

Your suggestions have been very far off the mark and have done little more than create the potential for confusion. While I appreciate that you are trying to help, you're making it much harder for those of us with wrenching experience to give advice to the OP. If you want to learn, that's great, but making random suggestions about parts that cannot possibly cause what the OP has described doesn't help you learn and it doesn't help the OP.

ZV

 

[ino uno soweno]

Yes, I guess.

But there still isn't a choke on modern passenger cars anymore, except in very backward countries with very far behind car factories and non existent smog regulations.

Or on a pretty old car.

There is one on my lawn mower, though.

Wiki:

Carburetors were the usual method of fuel delivery for most US-made gasoline-fueled engines up until the late 1980s, when fuel injection became the preferred method.[7] In the U.S. market, the last carbureted cars were:

1990 (General public) : Oldsmobile Custom Cruiser, Buick Estate Wagon, Cadillac Brougham, Honda Prelude (Base Model), Subaru Justy
1991 (Police) : Ford Crown Victoria Police Interceptor with the 5.8 L (351 cu in) engine.
1991 (SUV) : Jeep Grand Wagoneer with the AMC 360 engine.
1993 Mazda B2200 (Light Truck)
1994 (Light truck) : Isuzu[8]

In Australia, some cars continued to use carburetors well into the 1990s; these included the Honda Civic (1993), the Ford Laser (1994), the Mazda 323 and Mitsubishi Magna sedans (1996), the Daihatsu Charade (1997), and the Suzuki Swift (1999). Low-cost commercial vans and 4WDs in Australia continued with carburetors even into the 2000s, the last being the Mitsubishi Express van in 2003.[citation needed] Elsewhere, certain Lada cars used carburetors until 2006. Many motorcycles still use carburetors for simplicity's sake, since a carburetor does not require an electrical system to function. Carburetors are also still found in small engines and in older or specialized automobiles, such as those designed for stock car racing, though NASCAR's 2011 season was the last one with carbureted engines; electronic fuel injection was used beginning with the 2012 race season.[9]

Yes, I suppose we are dammed if we do, and dammed if we don’t, '


But, they just keep putting in that word,



That was a good read too, the Auss cars ring true, thanks,

 

[SAWYER]

I replaced the thermostat and it still does it.

 

[JCH13]

A failed thermostat would make the car overheat all the time, especially when under load, not just when it's idling.

Edit: Did you refill and bleed the cooling system after replacing the thermostat?

Ensure your water pump belt is tight.

Flush, refill, and bleed the cooling system (or have a garage else do it).

Try compression test.

Use a kit to check for combustion gases in your coolant.

Any of the above would be informative for you to try before throwing more parts at your car.

Another Edit: do you know that your cooling fans are turning on?

 

[SAWYER]

My front two fans are on and I have not flushed and bleed the system

 

[JCH13]

My front two fans are on and I have not flushed and bleed the system

First part is good.

Second part is really bad. You have no doubt introduced air into your cooling system and must, repeat, MUST bleed your cooling system of air to prevent a more serious malfunction.

Some cars can be tolerant of air in the cooling system, to a degree, but others can have air pockets develop around the coolant sensor(s) and then the fans won't even kick on under certain circumstances.

 

[SAWYER]

OK how exactly do I flush? Just drain the radiator?

 

[JCH13]

This is how.

 

[hanoverphist]

my money is still on either water pump or head gasket. my 98 civic ended u with a small break in the intake manifold gasket that was leaking coolant into the intake. didnt run rough or anything, but was losing coolant steadily. was being driven by an inexperienced teen, she didnt realize it and ended up toasting the motor. that motor had originally had a HG issue that was causing the exact symptoms the OP has. changed the HG out, did the water pump, timing belt and tensioners while the head was off and it was all good. took her a year to blow the motor after that.

 

[Zenmervolt]

my money is still on either water pump or head gasket. my 98 civic ended u with a small break in the intake manifold gasket that was leaking coolant into the intake. didnt run rough or anything, but was losing coolant steadily. was being driven by an inexperienced teen, she didnt realize it and ended up toasting the motor. that motor had originally had a HG issue that was causing the exact symptoms the OP has. changed the HG out, did the water pump, timing belt and tensioners while the head was off and it was all good. took her a year to blow the motor after that.

Ditto this. Either the water pump's not flowing enough at idle or the head gasket is starting to fail and you're getting some combustion gasses in the cooling system which creates an air pocket.

The OP needs to bleed the system and then see if the symptoms return/continue.

ZV