Go Back   Honda-Tech > Honda and Acura Model-Specific Technical Forums > Honda Civic/Del Sol (1992 - 2000)
Sign in using an external account
Register Forgot Password?
Search


Welcome to Honda-Tech!
Welcome to Honda-Tech.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Honda-Tech community today!


Reply
 
 
 
submit to reddit
 
LinkBack Thread Tools Search this Thread
Old 12-13-2011, 06:28 PM   #1
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Temperature Gauge Fluctuates 1-2 bars

So recently with the cold weather here (20 degrees in the morning), I have noticed that on my hour and a half drive to work, my temperature gauge would fluctuate 1-2 bars below the spot where the needle normally sits in the middle area.

This only happens while going on long straight roads, highways, or coasting downhill (still in gear while coasting, not in neutral, downshifting). The needle will never get close to cold, just 2 bars, maybe 3 at the most towards cold from the normal middle area.

Would a stuck open thermostat cause this? Does it sound like I have a stuck open thermostat?

Some facts:
-In stop and go, city traffic, the needle stays at normal spot and would move down 1 bar (if I hit a long straight) or not at all.
-The needle never goes towards hot.
-My heater is always on and it's always hot and never gets cold.
-On a cold start/fast idle and waiting 5-7 minutes after start up, my top radiator hose starts to get warm/hot, the bottom radiator hose is cold. The heat coming out the vents blows warm-hot as the car warms up.
-Once I get to work after driving for over an hour, both the top and the bottom radiator hoses are the same hot temperature by feel.
-No coolant loss. Reservoir stays the same level.

Other facts:
-Car is a 2000 Honda Civic SI.
-I changed out the radiator last winter with a Koyo OEM replacement (identical to stock), but the core is bigger (maybe twice the size or less) than the old OEM radiator.
-Used Honda Type 2 blue antifreeze.
-New radiator hoses also changed.
-Bled/burped the cooling system with a bleed funnel kit similar to this:
Click the image to open in full size.
-I made sure the air bubbles came out by "massaging" the radiator hoses.
-Heat was on hot and on high setting.
-Bled the cooling system till the radiator fan kicked on and off at least 5 times.

I am going to bleed the system just to see if it helps whenever I get time. I already ordered a OEM Honda thermostat since it's cheap but I wanted to see what you guys think.
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-14-2011, 08:20 AM   #2
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

I am not sure what the problem is?

As long as you are getting heat and it running half way or lower you are ok.

To play it safe do the thermostat.
motegicivic is offline   Reply With Quote
Old 12-14-2011, 08:28 AM   #3
Honda-Tech Member
 
sfar785's Avatar
 
Join Date: Nov 2009
Location: Oklahoma
Posts: 328
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

came into thread, saw Nissan motor, srsly just wtf'd
__________________
'09 Honda Fit Sport - bone stock
'93 Civic EJ8 - B18B1 swap
'87 Mazda RX-7 - NA
sfar785 is offline   Reply With Quote
Old 12-14-2011, 08:51 AM   #4
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by sfar785 View Post
came into thread, saw Nissan motor, srsly just wtf'd
He was just showing the type of funnel he used, that is not his car.
motegicivic is offline   Reply With Quote
Old 12-14-2011, 09:06 AM   #5
Honda-Tech Member
 
sfar785's Avatar
 
Join Date: Nov 2009
Location: Oklahoma
Posts: 328
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

lol i know, but the pic was the first thing that i saw
__________________
'09 Honda Fit Sport - bone stock
'93 Civic EJ8 - B18B1 swap
'87 Mazda RX-7 - NA
sfar785 is offline   Reply With Quote
Old 12-14-2011, 09:30 AM   #6
Honda-Tech Member
 
MonkeyBoy668's Avatar
 
Join Date: Mar 2004
Location: Suburbia
Posts: 870
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

It certainly sounds like your thermostat could be failing open. Usually when they fail the spring doesn't push open the valve as far as it should (or not at all), but sometimes they fail in such a way they they don't close beyond a certain point, so they're running partially to fully open.

I had a similar problem in the winter a couple years ago, around town on side streets everything was fine, but once I got on the highway the needle would slowly drop, and the faster I went the lower it got.

Is there any correlation between your average speed and how low the needle gets?
MonkeyBoy668 is offline   Reply With Quote
Old 12-14-2011, 09:54 AM   #7
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by MonkeyBoy668 View Post
It certainly sounds like your thermostat could be failing open. Usually when they fail the spring doesn't push open the valve as far as it should (or not at all), but sometimes they fail in such a way they they don't close beyond a certain point, so they're running partially to fully open.

I had a similar problem in the winter a couple years ago, around town on side streets everything was fine, but once I got on the highway the needle would slowly drop, and the faster I went the lower it got.

Is there any correlation between your average speed and how low the needle gets?
Can the thermostat fluctuate, say it opens at highway speeds and then close again or does it stay open at temperature?
motegicivic is offline   Reply With Quote
Old 12-14-2011, 10:23 AM   #8
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by MonkeyBoy668 View Post
It certainly sounds like your thermostat could be failing open. Usually when they fail the spring doesn't push open the valve as far as it should (or not at all), but sometimes they fail in such a way they they don't close beyond a certain point, so they're running partially to fully open.

I had a similar problem in the winter a couple years ago, around town on side streets everything was fine, but once I got on the highway the needle would slowly drop, and the faster I went the lower it got.

Is there any correlation between your average speed and how low the needle gets?
If my thermostat is partially stuck open, would the bottom radiator hose warm up the same or slow rate as the top radiator hose in cold start/fast idle? Because when I checked it the other morning after 5-7 minutes of warming up in 20 degree coldness, my bottom hose was cold while the top was getting warm/hot.

I would say there isn't a correlation between speed and needle movement. I can be cruising 65 mph on the highway or 45 mph on a straight backroad and it won't move at all. If it does move, it slowly moves down like a bar or two but it does this over a long period of time.

I do notice that when I am coming to a stop going downhill, the needle moves down 2 bars quickly.

Quote:
Originally Posted by motegicivic View Post
Can the thermostat fluctuate, say it opens at highway speeds and then close again or does it stay open at temperature?
I always thought once it opens after operating temp, it stays open.
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-14-2011, 10:30 AM   #9
Honda-Tech Member
 
Wrona's Avatar
 
Join Date: Jul 2010
Location: Denver, Colorado
Posts: 2,125
iTrader Rating: (0)
Wrona92
Default Re: Temperature Gauge Fluctuates 1-2 bars

you are probably looking at a new Honda thermostat...what happened to my car is just that except my temp gauge would be barely off the line the car would not overheat there was just no heat coming out of the vetns got a new thermostat now it sits perfectly at where my integra sits at where it used to be
__________________
Quote:
Originally Posted by Cairo-Honda View Post
Are the pistons in B16A and B16A auto manual are different?
Quote:
Originally Posted by Freshdot View Post
totally different, they also have diff flux capacitors.
Quote:
Originally Posted by Cairo-Honda View Post
Sorry, what is "diff flux capacitors"??
Wrona is offline   Reply With Quote
Old 12-14-2011, 06:05 PM   #10
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

My heat coming out the vents warm up normally and stays hot though.

It's weird. On my commute home tonight, the temp gauge went to the normal spot and didn't change until I was almost home coming down a steep hill. Was downshifting and coasting. As soon as I got back on the gas and started driving, the temp gauge started to go back to normal and stayed there.

My thermostat should be here tomorrow so I'll change it out when I get a chance.
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-14-2011, 07:11 PM   #11
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Does your temp gauge act normally? Does it gradually raise as the car warms up? Then when you shut the car off does it drop down?

The gauge does not bounce if you hit bumps etc.
motegicivic is offline   Reply With Quote
Old 12-14-2011, 07:57 PM   #12
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by motegicivic View Post
Does your temp gauge act normally? Does it gradually raise as the car warms up? Then when you shut the car off does it drop down?

The gauge does not bounce if you hit bumps etc.
Yes, the gauge gradually rises as the engine warms. This morning, I let it warm up to a 1-2 bars above C before driving off. Heat was was warm and rising as I was driving. Engine was at operating temp 5-10 minutes later when I stopped at the gas station.

The gauge does drop down when the engine is shut off. The gauge also doesn't move when I go over bumps.
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-23-2011, 05:39 AM   #13
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

So I changed out the thermostat with an OEM Honda one, bled the cooling system, and the fluctuation has gone away. The gauge stays pegged in the normal spot and doesn't move while driving. The heat seems to be blowing hotter also.

I also took the old thermostat and put it in boiling water to test it. It opened all the way and closed all the way when I took it out of the boiling water. I also did a test of leaving the thermostat in the pot of boiling water then letting it simmer. The thermostat opened all the way and didn't react to the water coming to a simmer. Is that normal or should the thermostat start to contract to the water simmering?
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-23-2011, 11:57 AM   #14
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by Si_chRis View Post
So I changed out the thermostat with an OEM Honda one, bled the cooling system, and the fluctuation has gone away. The gauge stays pegged in the normal spot and doesn't move while driving. The heat seems to be blowing hotter also.

I also took the old thermostat and put it in boiling water to test it. It opened all the way and closed all the way when I took it out of the boiling water. I also did a test of leaving the thermostat in the pot of boiling water then letting it simmer. The thermostat opened all the way and didn't react to the water coming to a simmer. Is that normal or should the thermostat start to contract to the water simmering?
I do not think it is that smart to react it is mechanical, basically opens and closes.

I think sometimes with age they can get lazy, maybe not open fully or fluctuate I recently did mine as well, I would get periodic running hot at idle (like once a month), been a few weeks so I am hoping that was the problem.

Was the one your took out oem?
motegicivic is offline   Reply With Quote
Old 12-24-2011, 05:56 PM   #15
Honda-Tech Member
 
Si_chRis's Avatar
 
Join Date: Mar 2006
Location: NorthEast
Posts: 1,994
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by motegicivic View Post
Was the one your took out oem?
Yes, the old thermostat removed was OEM Honda. I don't know if the numbers stamped on it (aside from 78 degree celsius) means the manufactured date, but if it is, it's the original one.
__________________
2000 FBP EM1
Si_chRis is offline   Reply With Quote
Old 12-24-2011, 06:34 PM   #16
Honda-Tech Member
 
Join Date: Jun 2011
Posts: 2,216
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

Quote:
Originally Posted by Si_chRis View Post
Yes, the old thermostat removed was OEM Honda. I don't know if the numbers stamped on it (aside from 78 degree celsius) means the manufactured date, but if it is, it's the original one.
So that is about 170 degrees.

I hope mine does the trick, mine is OEM as well.
motegicivic is offline   Reply With Quote
Old 12-25-2011, 12:49 PM   #17
Honda-Tech Member
 
Join Date: Nov 2011
Posts: 5
iTrader Rating: (0)
Default Re: Temperature Gauge Fluctuates 1-2 bars

I think i have to do the same thing because when it is cold out it takes my temp gauge a while to get to normal operating temp.
vanboxer is offline   Reply With Quote
 
 
 
submit to reddit
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Cooling problems on ITR Fink2iCe Acura Integra Type-R 9 01-09-2011 02:06 PM
Heater will not blow warm or hot air nitewolf Honda Civic/Del Sol (1992 - 2000) 15 10-28-2010 06:15 PM
Both radiator hoses are hot.. is that normal? hybrid90 Tech/Misc 2 09-15-2008 11:51 PM
Always running cold? eg6.vtec Honda Civic/Del Sol (1992 - 2000) 8 06-09-2008 06:24 PM
Overheating problem - Changed thermostat, bled the system, new radiator cap.. What's wrong? I3ooS710 Honda Civic/Del Sol (1992 - 2000) 69 06-17-2006 09:10 AM


Tags
accord, added, antifreeze, car, drops, gauge, guage, honda, make, middle, needle, normal, radiators, temp, temperature

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 08:02 AM.



2014 Copyright, InternetBrands Inc.
Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.
Emails & Contact Details