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Thermostat, sensor, and revving

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  #1  
Old 01-02-2012, 11:32 AM
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Default Thermostat, sensor, and revving

Hello Honda enthusiasts. My first thread!
I have a 1995 Accord v-tec 4 cyl that I am trying to problem solve for and not a mechanic. It takes a long time (around 15 minutes) to move the temp gauge to the blue line and it will not go above unless I stop, put in park, and idle. Then, the gauge moves to about 1/2 way between the blue line and mid-level. At the same time, the idle revs and eases, revs and eases, finally settling down. I drove it with the heater off the last time and the gauge level did not drop down so dramatically from 1/4 to the bottom so fast. Is this some sort of a sender/sensor problem?
Help!

bob a
 
  #2  
Old 01-02-2012, 12:04 PM
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Sounds like possible two issues.
1) Low coolant or trapped air
2) stuck open t-stat

EDIT: BTW, I moved this to Gen Tech....fits better here.......welcome and thanks for joining
 
  #3  
Old 01-03-2012, 06:42 PM
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Thanks pm212. I replaced the temp sensor under the distributor (the one with two wires) and bled the air out of the system. It is running better but not getting up to temp fast enough for me. If you agree that the thermostat is still probably open, that is an easy fix too. Thanks again!
 
  #4  
Old 01-03-2012, 07:01 PM
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Still sounds like low coolant and or a stuck open t-stat....more towards the t-stat than anything.

If you replace the t-stat, be sure to bleed the air out when you re-fill the coolant.

BTW- the one under the dist with ONE wire drives the gauge. Sounds like you replace the ECT that tells the computer what temp the coolant is.
 
  #5  
Old 01-05-2012, 05:31 PM
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Well, got the thermostat changed and the temp gauge is showing perfect and steady at around 1/4 level. Thanks a ton for the help. Since this is my daughter's car and she is often away at college, I don't get much time to keep it going. Now, I am realizing that the cooling fans do not turn on at all unless the air conditioner is going. I will look at some threads on this subject but if you have any ideas, I am all ears. Thanks again for the therm suggestion.

bob a
 
  #6  
Old 01-05-2012, 07:56 PM
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Cool, one issue down.

As a test. There is a two wire green connector on the t-stat housing. Pull the connector and jump the wires (not switch the connector with the wires) with a paperclip or something, turn the car to "on"/pos II and see if BOTH fans come on?

Not sure where you live but this time of the year (in north america) it could take 20~30 min of idle time before the engine gets warm enough for the fans (notice both) to cycle.

EDIT: See pic for location.....and yes the vtec was leaking on mine but I fixed it...in case anyone makes a comment.
 
Attached Thumbnails Thermostat, sensor, and revving-5th-gen-fan-switch.jpg  

Last edited by poorman212; 01-05-2012 at 08:03 PM.
  #7  
Old 01-05-2012, 09:39 PM
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PM212,
After I read another thread and double checked to make sure I had no air in the system with the bleeding procedure, I found no air in system for sure. Took the car on a 20 minute drive around town, then parked it for about 7 minutes in the driveway, still no fans on. So, I jumped the connector at the T-stat and both fans came on. I plugged the connector back into the pins, wondering if it was possibly a loose connection but no difference. I am guessing now that I have to look at a new switch in the thermostat? BTW, I am in Colorado and it was warm here today, around 62 degrees! I did try out the A/C today and both fans came on for that action
Thanks again for your help, I really appreciate it. More ideas?

bob
 
  #8  
Old 01-06-2012, 12:37 AM
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Is the temperature gauge in the car rising past the half-way mark when it is idling?
 
  #9  
Old 01-06-2012, 09:13 AM
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No, the gauge reads 1/4 at the highest and pretty much stays there once the car warms up. I am guessing this is a level that is okay and the fans only kick on when the gauge reaches near or above 1/2 level? Thanks for your help.

bob
 
  #10  
Old 01-06-2012, 09:50 AM
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The fans will kick on when the temperature reaches around 200 degrees. If you let the car idle long enough, the fans should turn on. You may have to run the engine at 2000 rpm at idle to get the coolant past 200.
 


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