DIY Coolant Temperature Sensor change (PICS)
06-05-09, 03:18 PM
#78
I am next up for this experiment.
I will be making the change to 3 different year LS sedans. A 90,94 & 96.
All have the orignal sensor deployed.
The 94 will also get its Fuel Filter changed.
I pick up the oem parts on Monday & will let you know how it goes.
I will be making the change to 3 different year LS sedans. A 90,94 & 96.
All have the orignal sensor deployed.
The 94 will also get its Fuel Filter changed.
I pick up the oem parts on Monday & will let you know how it goes.
06-09-09, 12:11 AM
#80
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Thanks for the write-up! 
I am going to have to tackle this over the weekend and see if I notice a change. Prolly gonna do the fuel filter & spark plugs/wires as well, but may wait a week to see if I notice any difference with just the sensor.
I am going to have to tackle this over the weekend and see if I notice a change. Prolly gonna do the fuel filter & spark plugs/wires as well, but may wait a week to see if I notice any difference with just the sensor.
06-10-09, 06:16 PM
#83
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I have a 1998 LS400. I identified the location of the sensor on the passenger side below the accelerator cable between the throttle body and the rectangular box connected to the intake air connector. Has anyone been able to replace the sensor without removing the intake air connector? 
By the way, the service manual says to torque the sensor to 20 N-m (14 ft-lb) [2000 manual, SF-78 to 80, 1394-6]. Thanks.
By the way, the service manual says to torque the sensor to 20 N-m (14 ft-lb) [2000 manual, SF-78 to 80, 1394-6]. Thanks.
Last edited by GrayLS400; 06-10-09 at 07:29 PM.
06-11-09, 03:07 PM
#84
One of the 3 down.
I broke the plastic portion off from the brass part of the old sensor after I had removed it from the block. It was brittle & cracked easily & what you see when look inside does not appear to be very conductive. Heavy oxidation throughout.
My 210,000 mile fuel filter also looked horrible.
89422-20010 Sensor
23300-50020 Fuel Filter
I broke the plastic portion off from the brass part of the old sensor after I had removed it from the block. It was brittle & cracked easily & what you see when look inside does not appear to be very conductive. Heavy oxidation throughout.
My 210,000 mile fuel filter also looked horrible.
89422-20010 Sensor
23300-50020 Fuel Filter
Last edited by damon; 06-11-09 at 03:46 PM.
06-19-09, 02:20 PM
#85
The 94 & 96 are now done. This is much easier on a UCF-20!
Both start much easier & seem to have much smoother throttle response. It really almost gives one the sense that you have made an ignition improvement of some kind.
The 96 sensor showed no where near the damage that the 94 sensor seemed to have.
Both start much easier & seem to have much smoother throttle response. It really almost gives one the sense that you have made an ignition improvement of some kind.
The 96 sensor showed no where near the damage that the 94 sensor seemed to have.
Last edited by damon; 06-20-09 at 03:02 PM.
06-23-09, 05:22 AM
#86
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Data point here:
I just did this on my garage-queen 85k mile '96 LS400. It made an immediately noticeable difference, with more power all over the RPM range.
Before I replaced the sensor, I compared the two side-by-side with a meter. I don't remember the scale I had it on, but I had both the original sensor and a new OEM sensor in a cup of boiling water. The old one read .40 and the new one read .45, so there is a measurable difference between the two.
33H4w
I just did this on my garage-queen 85k mile '96 LS400. It made an immediately noticeable difference, with more power all over the RPM range.
Before I replaced the sensor, I compared the two side-by-side with a meter. I don't remember the scale I had it on, but I had both the original sensor and a new OEM sensor in a cup of boiling water. The old one read .40 and the new one read .45, so there is a measurable difference between the two.
33H4w
Last edited by bmoore; 04-17-10 at 05:53 AM.
06-30-09, 01:45 AM
#88
I just replaced the sensor on my 95 with 190,000kms, used genuine toyota/lexus part, didnt really notice a difference. The car always ran great. I checked the gas mileage and it was 10.4L/km - 24mpg on a 400km highway drive, this is the best ever by a small margin but i've also done the exhaust lately so i guess that's got more to do with it
08-14-09, 08:02 AM
#90
Are you all draining your coolant before doing this? The Lexus instructions say to do this but it appears that you guys are not.
I'm conflicted on whether or not to do this. My 2000 LS has 130,000 miles, but runs great and gets good gas mileage. Kind of a "if it's not broke don't fix it" deal.
I'm conflicted on whether or not to do this. My 2000 LS has 130,000 miles, but runs great and gets good gas mileage. Kind of a "if it's not broke don't fix it" deal.