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Old 07-01-14, 01:31 AM   #196
simrx3
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hi,

well i just had my mileage drop off

went from 10.6litres per 100km to 12.2 litres per 100km..

read this a little while ago and remembered it.

bought the sensor and took mine out..

it was stuffed.. the plastic had crystallised and was really brittle..

ive just put the new one in..

so will let yous know if it fixed it..
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Old 02-14-15, 10:37 PM   #197
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I have noticed that temp gauge changes after driving the car for a trip of 1 hour and 30 minutes
So in first 30 minutes of the trip it was between second and third line, while after one hour it was a little above third line, and finally when i reached my destination it was again between second and third line!

Is it thermostat or the ECT?
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All LS400 owners with bad gas mileage READ THIS!-first.jpg   All LS400 owners with bad gas mileage READ THIS!-second.jpg   All LS400 owners with bad gas mileage READ THIS!-third.jpg  
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Old 02-15-15, 07:56 AM   #198
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Quote:
Originally Posted by qewani1 View Post
I have noticed that temp gauge changes after driving the car for a trip of 1 hour and 30 minutes
So in first 30 minutes of the trip it was between second and third line, while after one hour it was a little above third line, and finally when i reached my destination it was again between second and third line!

Is it thermostat or the ECT?
Didn't you read the temperature using an OBD-II tool?
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Old 02-15-15, 12:13 PM   #199
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It looks like you thermostat might be stuck open. Like Yamae suggested you should buy a cheap obd-II tool to read the actual temp though.
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Old 02-15-15, 10:04 PM   #200
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Quote:
Originally Posted by Yamae View Post
Didn't you read the temperature using an OBD-II tool?
Again went for a trip of 2 hours during night where outside temp was 18, but this time took my OBD2 scanner to read the ECT values.. I have noticed that Temp gauge drops only when car is moving, but on idle it reads 77, while when car moving it reads lower 70 !!
As am seeing, temp gauge is reading the actual values.., so it means ECT is working fine
Is that normal?
attaching below the readings...
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All LS400 owners with bad gas mileage READ THIS!-img_3156.jpg   All LS400 owners with bad gas mileage READ THIS!-img_3157.jpg   All LS400 owners with bad gas mileage READ THIS!-img_3154.jpg  
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Last edited by qewani1; 02-15-15 at 10:08 PM..
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Old 02-16-15, 06:07 PM   #201
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After 2 hours of driving the temp should be around 180-190 degrees which would be the cars operating temperature. if it's only reading 77 then dropping to 70 then the car is not heating up properly and thats probably because your thermostat is stuck open. If your coolant was low you would be overheating instead the car is not even getting to operating temp. Does your heat blow hot or warm?
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Last edited by sha4000; 02-16-15 at 09:13 PM..
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Old 02-16-15, 08:48 PM   #202
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Quote:
Originally Posted by qewani1 View Post
Again went for a trip of 2 hours during night where outside temp was 18, but this time took my OBD2 scanner to read the ECT values.. I have noticed that Temp gauge drops only when car is moving, but on idle it reads 77, while when car moving it reads lower 70 !!
As am seeing, temp gauge is reading the actual values.., so it means ECT is working fine
Is that normal?
attaching below the readings...
As I told you 2 weeks ago.
http://www.clublexus.com/forums/ls40...ml#post8898726

It may shorten your engine life to run highway with a low temp condition. It's also bad for the gas mileage. You'd better fix it quickly.
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Old 02-16-15, 10:14 PM   #203
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Quote:
Originally Posted by sha4000 View Post
After 2 hours of driving the temp should be around 180-190 degrees which would be the cars operating temperature. if it's only reading 77 then dropping to 70 then the car is not heating up properly and thats probably because your thermostat is stuck open. If your coolant was low you would be overheating instead the car is not even getting to operating temp. Does your heat blow hot or warm?
180-190 degrees fahrenheit or celsius ?
The temperatures which i mentioned in my previous post are in Celsius, during the day driving the temp needle reads 85 Celsius, what i mentioned is only during night driving
heat blows hot

Quote:
Originally Posted by Yamae View Post
A slow temperature rise is mostly caused by a worn thermostat. The ECT sensor only detects the temperature. It doesn't have a long time constant. It only has about 10 seconds of it.
As per your old post Do you recommend me to change the thermostat ?
My current highway MPG is 20 only!
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Last edited by qewani1; 02-16-15 at 10:18 PM..
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Old 02-17-15, 05:29 PM   #204
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I was talking about Fahrenheit so if it's 85 Celsius then the car is getting to operating temp. i would change the thermostat . It's a cheap and easy fix.
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Old 02-17-15, 06:01 PM   #205
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Quote:
Originally Posted by qewani1 View Post
As per your old post Do you recommend me to change the thermostat ?
My current highway MPG is 20 only!
The early bird gets the worm. A slow fix damages the car more and looses the money. If I were you, I would enjoy better drive feeling and better gas mileage changing the thermostat quickly. Improved gas mileage would be quickly more than the cost of the thermostat and that $ will be added more and more in the future.
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Old 02-17-15, 09:34 PM   #206
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could i have the OEM part numbers of the Thermostat and gasket for LS400 2000?
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