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D17VTECPOWER threads consolidated - how a member should not behave
07-29-2018
#1923
Running hot at idle. Bad water pump?
My Civic just started running hot at idle. What it does is it heats up to around 230 degrees at idle after a few minutes. It seems to overheat quicker if the AC is on and/or if it is idling in drive. But if I raise the RPM slightly to around 1200 RPM or higher, the temp comes down to a normal 180-200 within about 20 seconds, and it stays normal unless it's idling. I did a test where I sprayed the radiator with cool water while the engine was idling to see if it would still overheat, and it still overheats even with cool water running over the radiator. The car has a Mishimoto racing radiator, the coolant is clean and full, there is no air in the system, both fans are running, there are no airflow obstructions in front of the radiator, and the thermostat and water pump have been replaced about 1 year ago. The thermostat is OEM Honda, and the water pump is made by Gates. I am thinking that the water pump is bad and not circulating enough coolant through the system at idle to keep the engine cool. Does that sound reasonable? Thanks.
07-30-2018
#1924
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Re: Running hot at idle. Bad water pump?
sticking thermostat would be my guess. recommend you replace it with a stant superstat or another OEM or any other non-failsafe type
Last edited by RobertD; 07-30-2018 at 09:46 AM.
07-30-2018
#1926
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Rep Power: 77 Re: Running hot at idle. Bad water pump?
i have had sticking thermostats where i would rev the engine a couple times, and then watch the temp drop, similar to what you describe
07-30-2018
#1927
Re: Running hot at idle. Bad water pump?
The other thing I just noticed is that the heater won't work at idle either. I tried running the heater to see if it would still overheat, but the heater won't work unless I raise the RPM to around 1200 RPM or higher. Then the heater works great and it won't overheat.
Last edited by D17VTECPOWER; 07-30-2018 at 11:32 AM.
07-30-2018
#1929
If you think a good mechanic is expensive, try hiring a bad one
Re: Running hot at idle. Bad water pump?
Of your two guesses:
Thermostat is the cheapest and easiest to replace. Try it first.
If that doesn't solve your problem........then you can find out if replacing the aftermarket water pump will fix the problem (impeller clearance or wear or loose on shaft?)
Thermostat is the cheapest and easiest to replace. Try it first.
If that doesn't solve your problem........then you can find out if replacing the aftermarket water pump will fix the problem (impeller clearance or wear or loose on shaft?)
07-30-2018
#1931
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07-30-2018
#1932
If you think a good mechanic is expensive, try hiring a bad one
Re: Running hot at idle. Bad water pump?
You tell us.
Normally I would have guessed the radiator is low.....BUT
You already said "the coolant is clean and full, there is no air in the system" and so we all assume you already triple checked this TODAY before trying to figure if there's really another problem or not and making this thread
Normally I would have guessed the radiator is low.....BUT
You already said "the coolant is clean and full, there is no air in the system" and so we all assume you already triple checked this TODAY before trying to figure if there's really another problem or not and making this thread
07-30-2018
#1934
Re: Running hot at idle. Bad water pump?
You tell us.
Normally I would have guessed the radiator is low.....BUT
You already said "the coolant is clean and full, there is no air in the system" and so we all assume you already triple checked this TODAY before trying to figure if there's really another problem or not and making this thread
Normally I would have guessed the radiator is low.....BUT
You already said "the coolant is clean and full, there is no air in the system" and so we all assume you already triple checked this TODAY before trying to figure if there's really another problem or not and making this thread
07-30-2018
#1935
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Re: Running hot at idle. Bad water pump?
you can always test your thermostat to see if it's operating properly. All it takes is a pot of water and a thermometer.
I don't remember the set points of the top of my head, but pull your thermostat, pop it into a pot of water and heat it up on the stove. If i remember correctly, it should be fully open at like.. 185 or 195F. If it opens just fine, cut the heat and monitor temps. Should close by like.. 135? Something like that. If it's working fine, rule out thermostat failure.
Sure, you lose a bit of coolant, but it sounds like you should have some coolant on hand.
I don't remember the set points of the top of my head, but pull your thermostat, pop it into a pot of water and heat it up on the stove. If i remember correctly, it should be fully open at like.. 185 or 195F. If it opens just fine, cut the heat and monitor temps. Should close by like.. 135? Something like that. If it's working fine, rule out thermostat failure.
Sure, you lose a bit of coolant, but it sounds like you should have some coolant on hand.
07-30-2018
#1937
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Re: Running hot at idle. Bad water pump?
So, possible your heat valve is not opening so your not getting heat out of your core.
Also possible your waterpump impeller is slipping or otherwise out of spec, or big chunk of rtv is clogging something up and maybe your radiator is crusted up inside so much it’s not letting much fluid through without the extra pump pressure.
Your heater core could also be crusted up..
Also possible your waterpump impeller is slipping or otherwise out of spec, or big chunk of rtv is clogging something up and maybe your radiator is crusted up inside so much it’s not letting much fluid through without the extra pump pressure.
Your heater core could also be crusted up..
07-30-2018
#1938
Re: Running hot at idle. Bad water pump?
So, possible your heat valve is not opening so your not getting heat out of your core.
Also possible your waterpump impeller is slipping or otherwise out of spec, or big chunk of rtv is clogging something up and maybe your radiator is crusted up inside so much it’s not letting much fluid through without the extra pump pressure.
Your heater core could also be crusted up..
Also possible your waterpump impeller is slipping or otherwise out of spec, or big chunk of rtv is clogging something up and maybe your radiator is crusted up inside so much it’s not letting much fluid through without the extra pump pressure.
Your heater core could also be crusted up..
07-31-2018
#1939
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Rep Power: 485 Re: Running hot at idle. Bad water pump?
Didn't your company system explode on you fairly recently? Did you fix everything properly or more "good enough" fixing?
08-01-2018
#1941
What should exhaust smell like with no cat?
I have no catalytic converter on my car, and the exhaust apparently stinks. I never really noticed much smell, but I'm used to this car, and I don't have a great nose. But a friend with a great nose got stuck behind me in traffic while we were going to eat, and she told me that my car smells terrible to the point where she had to turn on recirculate and open the windows in the rain to get rid of the smell. Is that normal for a car with no cat, or is something wrong? I would think that a modern car shouldn't stink that bad if it is running correctly, even with no cat. Anyone know what it should smell like with no cat? Thanks.
08-01-2018
#1942
If you think a good mechanic is expensive, try hiring a bad one
Re: What should exhaust smell like with no cat?
Is that normal for a car with no cat
People like you are the reason so many places require emissions inspections.
(hugs a tree)
I would think that a modern car shouldn't stink that bad if it is running correctly, even with no cat.
Anyone know what it should smell like with no cat?
Also: Like any old lawnmower or other small engine that has no cat. But a car engine is bigger so there's a lot more of it.
The only thing that can really affect the "flavor" of the stink is the fuel you burn. I run 92-93 octane in my scoot and it smells a little different from the 87 in the lawnmower.
she told me that my car smells terrible to the point where she had to turn on recirculate and open the windows in the rain to get rid of the smell.
08-01-2018
#1943
Re: What should exhaust smell like with no cat?
ABSOLUTELY
People like you are the reason so many places require emissions inspections.
(hugs a tree)
Wrong.
Exactly what your car now smells like.
Also: Like any old lawnmower or other small engine that has no cat. But a car engine is bigger so there's a lot more of it.
The only thing that can really affect the "flavor" of the stink is the fuel you burn. I run 92-93 octane in my scoot and it smells a little different from the 87 in the lawnmower.
You should have been around back before the age of catalytic converters. The "stink" was impossible to escape, and if you were really sharp and sensitive you could tell if it was too rich or too lean by how bad it makes your eyes water. NOT KIDDING.
People like you are the reason so many places require emissions inspections.
(hugs a tree)
Wrong.
Exactly what your car now smells like.
Also: Like any old lawnmower or other small engine that has no cat. But a car engine is bigger so there's a lot more of it.
The only thing that can really affect the "flavor" of the stink is the fuel you burn. I run 92-93 octane in my scoot and it smells a little different from the 87 in the lawnmower.
You should have been around back before the age of catalytic converters. The "stink" was impossible to escape, and if you were really sharp and sensitive you could tell if it was too rich or too lean by how bad it makes your eyes water. NOT KIDDING.
08-01-2018
#1944
If you think a good mechanic is expensive, try hiring a bad one
Re: What should exhaust smell like with no cat?
Is a Flowmaster high flow cat okay?
08-01-2018
#1945
Re: What should exhaust smell like with no cat?
I expect that it will not fail due to a flaw for at least 5 years, I expect that it won't kill my power, and I expect that it will do a decent enough job at cleaning the exhaust that it won't **** off the PCM. Will it meet my expectations, and if not, what will? Thanks.
08-01-2018
#1946
If you think a good mechanic is expensive, try hiring a bad one
Re: What should exhaust smell like with no cat?
I expect that it will not fail due to a flaw for at least 5 years, I expect that it won't kill my power, and I expect that it will do a decent enough job at cleaning the exhaust that it won't **** off the PCM. Will it meet my expectations, and if not, what will? Thanks.
What's the warranty period on it?
How long do YOU need it to last?
08-01-2018
#1948
If you think a good mechanic is expensive, try hiring a bad one
Re: What should exhaust smell like with no cat?
5 year
08-01-2018
#1950
If you think a good mechanic is expensive, try hiring a bad one
Re: What should exhaust smell like with no cat?
but I don't want to pay to have it replaced 50 times either.
Grab an original cat from a low mileage car in a junkyard and bolt it on?
