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Replace coolant temp sensor?

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Old Sep 23, 2008 | 08:52 AM
  #1  
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From: Bardstown, KY
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Default Replace coolant temp sensor?

I will be taking out my newly installed 195* thermostat tonight so that I can replace the thermostat housing that I must have cracked when tightening the bolts even though I only torqued them to 20 ft/lbs. It was just old and brittle I guess.

Question is since I'm going to have to remove and reinstall the coolant temp sensor into the new housing, should I just go ahead and get a new sensor as well? What does this thing do other than feed the temp gauge and what happens if it fails?
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Old Sep 23, 2008 | 09:18 AM
  #2  
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Clean the old one and put it back in.

Teflon tape it...no dope though.

It triggers the fan and feeds the ECU for open/closed loop operation.

Also does the dash gauge.
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Old Sep 23, 2008 | 09:27 AM
  #3  
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Originally Posted by Bouncy
Teflon tape it...no dope though.
Thanks. I bought some stuff called thread sealant that appears to be for this use. Is it OK? I also have some white tape that a plumber would use. Is that better. It's not high temp or anything.

Also, what's the ECU open/closed loop deal? As long as I won't be stranded or do any damage if it fails, I'll just use the old sensor.
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Old Sep 23, 2008 | 10:15 AM
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Use the white plumbers tape b/c it works like anti-seize and the sealer works like loc-tite.
The open/closed loop thing is what the computer(ECU) does to timing and mixture to enhance MPG and improves emissions.
Old sensor should be fine to re-use.
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Old Sep 23, 2008 | 10:19 AM
  #5  
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Cool, saved me $5 on the thread sealer and $20 by using the old sensor. Thanks!
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Old Sep 23, 2008 | 12:20 PM
  #6  
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PM me for paypal instructions. We collect around here half of what we save people
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Old Sep 23, 2008 | 12:49 PM
  #7  
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Do you also reimburse half the cost of mods inspired by the forum as well? That'll put you in the hole!!!
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Old Sep 23, 2008 | 01:10 PM
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Originally Posted by 96 XJ Sport
Do you also reimburse half the cost of mods inspired by the forum as well? That'll put you in the hole!!!
Nope...Seeing a mod is YOUR addiction not mine. I only offer options to solve problems at cheap prices.
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Old Sep 23, 2008 | 07:22 PM
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For your addiction we do offer a 12 step program.

Step 1: Get lift
Step 2: Trim flares
Step 3: Get bigger tires
Step 4: Trim fenders
Step....

Well you get the idea
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Old Jul 31, 2011 | 10:16 PM
  #10  
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I have a quick question...I just replaced my water pump and t-stat and was wondering what would happen if I didn't install the t-stat back in the right way just like the old one was really didn't pay attention on how it was proped in there and also my gauge goes from the line above 210 and stays there but after driving around for awhile it will jump to the 260 and kick the idiot light on and stay there..but after you turn the car off and back on it goes right back to where it was running at...PS outside temperature has been 80+...live in Michigan.....thanks chris
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Old Jul 31, 2011 | 10:32 PM
  #11  
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Originally Posted by Howler_GT
For your addiction we do offer a 12 step program.

Step 1: Get lift
Step 2: Trim flares
Step 3: Get bigger tires
Step 4: Trim fenders
Step....

Well you get the idea
step 5 is bigger tires, 6 is more lift thats the step i'm on
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Old Aug 1, 2011 | 02:34 AM
  #12  
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Originally Posted by 99_Lifted_Cherokee
I have a quick question...I just replaced my water pump and t-stat and was wondering what would happen if I didn't install the t-stat back in the right way just like the old one was really didn't pay attention on how it was proped in there and also my gauge goes from the line above 210 and stays there but after driving around for awhile it will jump to the 260 and kick the idiot light on and stay there..but after you turn the car off and back on it goes right back to where it was running at...PS outside temperature has been 80+...live in Michigan.....thanks Chris
.

The big side should be in the engine. The more flat side should be out. Howlong do you turn it off for for it to go back?
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Old Aug 1, 2011 | 08:00 PM
  #13  
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Thad how I have it...right off the right back maybe 30 seconds
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Old Aug 1, 2011 | 08:02 PM
  #14  
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Could be the sending unit. Are all the other gauges working properly.
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Old Aug 1, 2011 | 08:13 PM
  #15  
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Did you burp the system?....kinda sounds like you have an air bubble in the system.
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