When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Just bringing this back to ask if anyone happens to know the exact amount of torque in ft-lbs for the ECU coolant temp sensor specified in the TSRM. Of course it's not supposed to be over-tightened but an official figure wasn't listed in the original post.
Just bringing this back to ask if anyone happens to know the exact amount of torque in ft-lbs for the ECU coolant temp sensor specified in the TSRM. Of course it's not supposed to be over-tightened but an official figure wasn't listed in the original post.
Thanks!
Should be 14 ft/lbs. I'll update the original post.
Edited: Also, I found this diagram (after I posted this I saw that your diagram also lists it on page 1 as well) which shows a small O-ring/gasket we need to pick up as well. I assume this is in addition to a very small wind of white plumber's tape on the threads. Someone already listed on page 2 that it's P/N 90430-12005.
Just so there is no confusion on this subject, the ECU pins out from 44B green wire to the 2 wire temp sensor and back thru brown wire thru pin 65B (or vice versa)
I have come across this post a couple of times looking for something and always get confused because the guy responds incorrectly that the ECU signal is a single wire and says he gets it from the Lexus manuals. Must have been referencing a different car. Just wanted to confirm this to anyone else who comes along. I am glad the OP stuck to his guns and argued the fact.
Sorry for reviving an old thread and this is my first post on the forum so apologies there as well but I want to change my coolant temp sensor. I've referenced the photos and found it but mine is a single wire. The other sensor next to it that I believe is to the gauge cluster is also a single wire. Mine is a 93 sc300 like @TheMole but I have a single wire which means single pin. Do I have the wrong one sensor or is my specific sc 1 in 1000?
Every 2jz I have seen has the 2 wire sensor towards the front of the motor (usually the 2 wire green connector on earlier SC's), and the 1 wire sensor is the one towards the middle of the motor.
what does the connector on your harness look like, is it a 2 wire plug or a 1 wire plug? does it look like its been rewired?
Interestingly, you are saying that a 1 wire sensor is installed in the spot towards the front of the motor?
that is a little odd because the 2 sensors have different thread sizes, so you cannot install them in the wrong spot if they are the right sensors for your car.
Now the sensors for non-vvti 2JZGE (92-97), vvti 2JZGE (98+), and 2JZGTE (turbo motors) are all slightly different threads and lengths, so its possible someone got the wrong one and just stuck it in there.
The one thing they all have generally have in common though is that the front one is a 2 wire for the ecu.
There may even be more variations in the later years for different models that do not use the same gauge cluster, like the cars that use the CAN system.. but that is not what's happening with yours.
now if the harness is just a 1 wire for some reason, and looks like its original, that would be surprising and maybe there is a variation we are not aware of.
the second wire is just a ground, and the 1 wire sensors ground through the engine block, so it would still sort of work but the resistance and ranges might be different.
when looking up coolant sensors for these engines, it is massively confusing.. and with how old these cars are, its very possible someone just installed the wrong sensor.
Every 2jz I have seen has the 2 wire sensor towards the front of the motor (usually the 2 wire green connector on earlier SC's), and the 1 wire sensor is the one towards the middle of the motor.
what does the connector on your harness look like, is it a 2 wire plug or a 1 wire plug? does it look like its been rewired?
Interestingly, you are saying that a 1 wire sensor is installed in the spot towards the front of the motor?
that is a little odd because the 2 sensors have different thread sizes, so you cannot install them in the wrong spot if they are the right sensors for your car.
Now the sensors for non-vvti 2JZGE (92-97), vvti 2JZGE (98+), and 2JZGTE (turbo motors) are all slightly different threads and lengths, so its possible someone got the wrong one and just stuck it in there.
The one thing they all have generally have in common though is that the front one is a 2 wire for the ecu.
There may even be more variations in the later years for different models that do not use the same gauge cluster, like the cars that use the CAN system.. but that is not what's happening with yours.
now if the harness is just a 1 wire for some reason, and looks like its original, that would be surprising and maybe there is a variation we are not aware of.
the second wire is just a ground, and the 1 wire sensors ground through the engine block, so it would still sort of work but the resistance and ranges might be different.
when looking up coolant sensors for these engines, it is massively confusing.. and with how old these cars are, its very possible someone just installed the wrong sensor.
Thats what i find is weird. It looks factory and its all in the wiring harness but i cant find anyone else who has it like this. Ive attached a picture from in between fuel injector 1 and 2 hopefully you can see down the center my hand holding it upward and that there is 1 plug/terminal/blade port (dont know the actual verbage, sorry) so I'll just shop around for one with the same thread pitch and single terminal and hope that sorts my a/f issues
I don’t know if this will help or not but my SC300 is also a 1993 model (California Emission spec but that makes no difference in this case) and since I have a lot of parts I am going through after dismantling the original engine I have both the ECU coolant temp sensor and the coolant temp gauge sender (the one with the metal spade) handy.
In my ‘93 2JZ-GE the ECU temp sensor has two pins.
When I last replaced mine I’ll tell you it was not the most fun to get to and I also opted not to drain the coolant so replacing it had to be done rather quickly to minimize coolant spillage.
I could be wrong but are you certain you haven’t gone far lower than where the ECU coolant temp sensor is located and instead pulled out the plug for the front knock sensor instead? That plug kind of looks like it’s for that and both 2JZ-GE knock sensors have only one wire.
Further down the block and closer to the front is yet another plug with one wire: your oil pressure sensor.
The ECU coolant temp sensor is futher up than both of those in a somewhat difficult to get to part of the front of your cylinder head on the intake side below the intake manifold (which is what is more or less making access a little challenging).
After looking at my engine I am pretty sure you are looking at the knock sensor like Kahn mentioned, or maybe the second one wire one towards the middle (under 2nd runner).
They are pretty close to each other and hard to see with all the stuff in the way. There should be a green 2 wire one pretty much under the number 1 runner.
This is a vvti 2jzge I am putting together, so the sensors are slightly different (single terminal changed shape) but the locations are the same for all 3.
Thank you both for your input. I took a third look at it and still couldnt see it so I put the flash on my phone and panned underneath it to see if I could see anything different. Luckily I did. Sneaky lil bugger is right under that first intake pipe. I saw on another thread someone pointed at that knock sensor I had unplugged and everyone agreed that was the coolant temp. dont believe every thread you read is the moral of this story I guess haha. Again thank you all for your input i really appreciate it
i'm responding this to clear up misinformation that Ali posted above, as i'm doing wiring for an SC300 customer right now.
SC300s have two coolant temp sensors:
one is for the ECU (2-wire) to know what temp the coolant is. (GREEN PLUG ON HARNESS)
one is for the gauge cluster (1-wire) so the oem coolant temp needle can sit in the middle. (BLACK PLUG ON HARNESS, or maybe gray)
GTEs don't have this same 1-wire sensor unless you have a 1jzGTE from a soarer.
IS300s also don't have it.
i'm responding this to clear up misinformation that Ali posted above, as i'm doing wiring for an SC300 customer right now.
SC300s have two coolant temp sensors:
one is for the ECU (2-wire) to know what temp the coolant is. (GREEN PLUG ON HARNESS)
one is for the gauge cluster (1-wire) so the oem coolant temp needle can sit in the middle. (BLACK PLUG ON HARNESS, or maybe gray)
GTEs don't have this same 1-wire sensor unless you have a 1jzGTE from a soarer.
IS300s also don't have it.
I will confirm . I have a couple of cars with the 2jzGTEs right now and they all have the 1 wire sensor for the gauge cluster . Both ECU / Gauge coolant sensors are on the upper coolant elbow on the left side of the engine .
I will confirm . I have a couple of cars with the 2jzGTEs right now and they all have the 1 wire sensor for the gauge cluster . Both ECU / Gauge coolant sensors are on the upper coolant elbow on the left side of the engine .
^^ Confirming the same on my SC's swapped in Non-VVT-i 2JZ-GTE engine. On that engine both sensors are located in exactly the same location that Gerry pointed out: on the upper coolant elbow (2JZ-GTE). As he states, the two-wire sensor gives the ECU its coolant temperature signal while the 1-wire sensor gives the dash coolant temp gauge it's own separate signal. However both the sensor part numbers are different for the 2JZ-GTE than they are for the more common USDM 2JZ-GE even though it's basically the same principle for both engines.
I'm not familiar with IS300 wiring harnesses so I can't comment there.
02-02-16, 04:25 PM
dont believe every thread you read is the moral of this story I guess haha. Again thank you all for your input i really appreciate it
. Both ECU / Gauge coolant sensors are on the upper coolant elbow on the left side of the engine .
