Go Back   Club Lexus Forums > Lexus Model Forums > SC Models > SC 400/300 > Performance & Maintenance
Sign in using an external account
Register Forgot Password?

DIY: Engine Coolant Temperature Sensor Replacement- 2jzge I6 SC300

Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
Old 07-08-09, 11:33 PM   #16
sc-driver
Lexus Test Driver
Trader Score: (7)
 
sc-driver's Avatar
 
Join Date: Oct 2006
Location: SoCal & SLOcal
Posts: 927
Default

Quote:
Originally Posted by gadgetSC View Post
The diagram of the head is incorrect. It shows an oil pressure sensor located to the right of the temp sensor. That is the location of the second temp sensor. There are 2, one (2)wire for the gauge cluster and one single wire for the ecu. The one you changed was for the gauge cluster.
The oil pressure sensor is located on the block. fyi
In my manual, it shows that the 2 wire one goes to the ecu. I'm pretty sure TheMole changed the right one.
This ad is not displayed to registered members.
Register your free account today and become a member on Club Lexus!

Last edited by sc-driver; 07-08-09 at 11:39 PM..
sc-driver is offline   Reply With Quote
Old 07-08-09, 11:44 PM   #17
sc-driver
Lexus Test Driver
Trader Score: (7)
 
sc-driver's Avatar
 
Join Date: Oct 2006
Location: SoCal & SLOcal
Posts: 927
Default

This is straight from the manual. Its kind of hard to see, but (1) points to the sensor on the left while (2) points to the sensor on the right. I also looked at the wiring diagram and there are 2 wires from the sensor that go to the ecu.
Attached Images
 
sc-driver is offline   Reply With Quote
Old 07-09-09, 07:43 AM   #18
gadgetSC
Lexus Test Driver
Trader Score: (0)
 
Join Date: Feb 2001
Location: NY/NV
Posts: 1,340
Default

Quote:
Originally Posted by sc-driver View Post
This is straight from the manual. Its kind of hard to see, but (1) points to the sensor on the left while (2) points to the sensor on the right. I also looked at the wiring diagram and there are 2 wires from the sensor that go to the ecu.
If you have the manual, post up the wiring diagram. I dont have access to my own and have been going of memory. I do know the the single wire input to the ecu comes in on pin 44B.
If you look in your manual at the wiring diagrams, you will find that the 2 wire sensor signal goes to the gauge cluster.
__________________
92 SC340 GT40R
00 SC300
gadgetSC is offline   Reply With Quote
Old 07-09-09, 03:56 PM   #19
sc-driver
Lexus Test Driver
Trader Score: (7)
 
sc-driver's Avatar
 
Join Date: Oct 2006
Location: SoCal & SLOcal
Posts: 927
Default

As you can see there is only one wire going to the combination meter (instrument panel) from the engine coolant temperature sender. The wiring diagram below that one shows how there are 2 wires from the engine coolant temperature sensor to the ecu.

Hope this clarifies any confusion.
Attached Images
 
sc-driver is offline   Reply With Quote
Old 07-09-09, 05:13 PM   #20
TheMole
Lexus Champion
Trader Score: (13)
 
TheMole's Avatar
 
Join Date: Oct 2006
Location: SoCal
Posts: 3,432
Send a message via AIM to TheMole
Default

Quote:
Originally Posted by sc-driver View Post
As you can see there is only one wire going to the combination meter (instrument panel) from the engine coolant temperature sender. The wiring diagram below that one shows how there are 2 wires from the engine coolant temperature sensor to the ecu.

Hope this clarifies any confusion.

Thanks for taking the time to post that up man, great work.
__________________
Electronic Dance Music Thread
05 Scion XB
99 Accord Coupe 5 speed - Sold on 3/28/2013
93 Black Onyx JZS147 - Sold on 9/12/2012
93 Diamond White Pearl JZZ31 - RIP on 09/02/2009
TheMole is offline   Reply With Quote
Old 07-10-09, 06:29 AM   #21
gadgetSC
Lexus Test Driver
Trader Score: (0)
 
Join Date: Feb 2001
Location: NY/NV
Posts: 1,340
Default

sc-driver, I have completely different diagrams from my manuals. What year manuals do you have? Seeing the p65 connection which is sensor ground does make sense. I will be sure to check my info when I can and will delete the above posts if I am incorrect. My intent is to make sure the correct information is presented so we can all benefit.
__________________
92 SC340 GT40R
00 SC300

Last edited by gadgetSC; 07-10-09 at 06:44 AM..
gadgetSC is offline   Reply With Quote
Old 07-10-09, 11:42 AM   #22
sc-driver
Lexus Test Driver
Trader Score: (7)
 
sc-driver's Avatar
 
Join Date: Oct 2006
Location: SoCal & SLOcal
Posts: 927
Default

It's all good! I've got the manual that applies to the 92-94 SC's. Which manual do you have?
sc-driver is offline   Reply With Quote
Old 07-25-09, 12:11 PM   #23
TheMole
Lexus Champion
Trader Score: (13)
 
TheMole's Avatar
 
Join Date: Oct 2006
Location: SoCal
Posts: 3,432
Send a message via AIM to TheMole
Default

Updated with my miles per gallon log. You guys can be the judge.
__________________
Electronic Dance Music Thread
05 Scion XB
99 Accord Coupe 5 speed - Sold on 3/28/2013
93 Black Onyx JZS147 - Sold on 9/12/2012
93 Diamond White Pearl JZZ31 - RIP on 09/02/2009
TheMole is offline   Reply With Quote
Old 07-25-09, 07:14 PM   #24
Ryeno
Banned
Trader Score: (3)
 
Join Date: Sep 2008
Location: NA
Posts: 1,262
Default

If i was reading that one post right then the car only uses the ECT sensor until it gets to operating temp to adjust the a/f mixture. Once it gets to temp, it uses the data from the maf and o2 sensors instead.
Ryeno is offline   Reply With Quote
Old 08-25-09, 06:44 PM   #25
7armani
Driver School Candidate
Trader Score: (1)
 
7armani's Avatar
 
Join Date: Jul 2008
Location: Tucson, AZ
Posts: 18
Default

I just bought the Toyota Tem sensor @ $63.13. It doesn't come with the copper gasket.
Went back again to Toyota and bought the gasket (90430-12005) @ $1.00. By the way I can't find the locaton of the Temp sensor. Appreciate if someone can snap a pictue on where it is on the SC300. (92 manual). thanks in advance.
7armani is offline   Reply With Quote
Old 08-26-09, 11:48 AM   #26
TheMole
Lexus Champion
Trader Score: (13)
 
TheMole's Avatar
 
Join Date: Oct 2006
Location: SoCal
Posts: 3,432
Send a message via AIM to TheMole
Default

Quote:
Originally Posted by 7armani View Post
I just bought the Toyota Tem sensor @ $63.13. It doesn't come with the copper gasket.
Went back again to Toyota and bought the gasket (90430-12005) @ $1.00. By the way I can't find the locaton of the Temp sensor. Appreciate if someone can snap a pictue on where it is on the SC300. (92 manual). thanks in advance.
Checkout post #17. The diagram shows if you are facing the left side of the engine and the sensor is #1. Shine a flashlight under the 1st intake runner and you should see a green connector.
__________________
Electronic Dance Music Thread
05 Scion XB
99 Accord Coupe 5 speed - Sold on 3/28/2013
93 Black Onyx JZS147 - Sold on 9/12/2012
93 Diamond White Pearl JZZ31 - RIP on 09/02/2009
TheMole is offline   Reply With Quote
Old 09-04-09, 07:19 PM   #27
7armani
Driver School Candidate
Trader Score: (1)
 
7armani's Avatar
 
Join Date: Jul 2008
Location: Tucson, AZ
Posts: 18
Default

Thanks. Mole. Found it. Its a really tight spot. No way take any pictures. Went ahead and bought some deep socket and extension. You have to buy the 1/2" drive cos the 3/8" drive deep socket was not deep enough. I broke the brittle connector tap while removing. Finally replaced it after 15 minutes and losing afew piece of skin. I took it for a test drive and noticed that its alittle more responsive and the idling is much smoother.
7armani is offline   Reply With Quote
Old 09-04-09, 08:15 PM   #28
TheMole
Lexus Champion
Trader Score: (13)
 
TheMole's Avatar
 
Join Date: Oct 2006
Location: SoCal
Posts: 3,432
Send a message via AIM to TheMole
Default

Quote:
Originally Posted by 7armani View Post
Thanks. Mole. Found it. Its a really tight spot. No way take any pictures. Went ahead and bought some deep socket and extension. You have to buy the 1/2" drive cos the 3/8" drive deep socket was not deep enough. I broke the brittle connector tap while removing. Finally replaced it after 15 minutes and losing afew piece of skin. I took it for a test drive and noticed that its alittle more responsive and the idling is much smoother.
Good to hear man. Hope your mpg increases a bit too!
__________________
Electronic Dance Music Thread
05 Scion XB
99 Accord Coupe 5 speed - Sold on 3/28/2013
93 Black Onyx JZS147 - Sold on 9/12/2012
93 Diamond White Pearl JZZ31 - RIP on 09/02/2009
TheMole is offline   Reply With Quote
Old 09-07-12, 10:53 AM   #29
spitfire7
Driver School Candidate
Trader Score: (0)
 
Join Date: Dec 2010
Location: ca
Posts: 38
Default

Would a bad ect cause your sc to have a stumble. Cut off while driving, and not start. Then start up just fine later?
spitfire7 is offline   Reply With Quote
Old 08-04-14, 11:57 AM   #30
jdmjoshi
Driver School Candidate
Trader Score: (0)
 
Join Date: Aug 2014
Location: Florida
Posts: 2
Default

Quote:
Originally Posted by TheMole View Post
Well after replacing the engine coolant temperature sensor on my friend's 1990 Camry and seeing the recent threads on the 1UZ-FE, I decided to change it on my 2jzge 1993 sc300. My sensor was probably original and the new part is not too expensive so why not?

I used the following:
Duralast (Autozone) part number: SU4007
Price: $29.99

If you want to use Toyota:
OEM part number: 8942220010
MSRP: $63.13
Online: ~$42 - $52

Many Lexus/Toyota vehicles use the same coolant temperature sensor so it should be easy to find.

PURPOSE
"The engine coolant temperature (ECT) sensor measures engine temperature by sensing water temperature. The ECM uses this information for determining the proper air/fuel mixture for all conditions." -via alldata.

If you know how to test it then refer to this:
Click the image to open in full size.


LOCATION
Green colored harness located under the front intake runner going into the block.

Click the image to open in full size.

Hope 93MSB doesn't mind me borrowing his pic from here: http://www.clublexus.com/forums/perf...-95-sc300.html


TOOLS NEEDED
-Ratchet and extension(s)
-Deep socket 19mm (Make sure it fits over the harness side of the sensor and reaches the bolt. I tested it on the new sensor first.)
-Drain pan (coolant will pour out)


STEPS
-(optional) Remove lower shield under the engine.

-(optional) Place drain pan under car because coolant will poor out once the sensor is removed. It may get messy so have some rags/paper towels ready to soak up excess coolant.

-(optional) If you have a container or pan that will fit under the sensor then it will be easier than removing the lower shield.

-Unplug harness from sensor. The area is pretty tight so I reached under with my right hand to press the release tab and used my left hand to pull on the harness. Came off easily once I got the technique down.

-Slip the deep socket 19mm over the sensor. Again, the area is pretty tight so it may take some wiggling around to get it on the bolt part. There were several times when I thought the socket was on the bolt, but it was only over the harness plug. Just keep pushing in and rotating the socket slowly until it catches since it is a snug fit.

-While removing the sensor, coolant will start pouring out. Have the new sensor out of the box and ready to install. You can also temporarily plug up the hole with your finger as you reach for the new sensor.

-Screw on the new sensor, tighten, and plug the harness back. Sorry I do not have the torque value, but just make sure you don't overtighten since the part is aluminum. Also, make sure it does not leak.


RESULTS and THOUGHTS
-As far as physical appearance, the old sensor did not look too bad after wiping some of the gunk off. It may have still worked fine.

-I have not noticed any significant performance gains in the last week since, but it seems to accelerate a bit easier. It can just be in my head though...

-I hope that it will improve my miles per gallon (mpg). I am still on the same tank so I will report back with any results.

UPDATE: 7/25/2009
-Here is my mpg log with brief descriptions. I'll let you guys decide if there are any differences after changing the sensor

Click the image to open in full size.



PICS
Old sensor with some gunk
Click the image to open in full size.

Old sensor after wiping off gunk
Click the image to open in full size.




Reference threads from the 1UZ-FE community:

http://www.clublexus.com/forums/perf...placement.html

http://www.clublexus.com/forums/ls40...ange-pics.html
The sensor I got a lil different
jdmjoshi is offline   Reply With Quote
Old 08-04-14, 11:57 AM
 
 
 
 
Reply

Tags
2jzge, 350, camry, coolant, coolent, ect, install, lexus, replacement, replacing, sc300, sensor, su4007, temperature, toyota

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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 Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY Coolant Temperature Sensor change (PICS) Zoraone LS400 221 08-31-14 11:33 PM
Hyperblink fix for 92-94 SC w/ 97 Taillights TheMole SC 400/300 70 03-13-14 09:11 PM
CA JDM Aristo Front Bumper Reinforcement TheMole 1Gen GS300 Classifieds (91-97) 0 04-14-13 05:35 PM
CA FS: Logitech Driving Force Pro PS2/3/PC TheMole General Classifieds 4 03-14-13 09:09 PM
SC300 Main Fuse TheMole SC 400/300 5 08-24-12 06:41 PM

All times are GMT -7. The time now is 03:42 PM.

Join ClubLexus
Advertising


Copyright © 2000-2008 Internet Brands, Inc. All Rights Reserved
Privacy Policy | Disclaimer | Terms of Use | JOBS


Get all contact info