TS2JZX MKIV SUPRA WIRING SPECIALTIES HARNESS

[JZJOE80]

Hey y’all, reached out to Link Ecu support earlier and they told me the water temp sensor on my car (factory sensor) can be used and read by the link ecu?  

Is this true, and if so does the oil pressure sensor also work the same. 

 

I ask because my tuner requested I run water temp sensor and pressure sensor for coolant and oil, but if the factory ones work I would prefer to leave it that way.

[Adamw]

They dont have oil pressure or coolant pressure connected to the ecu from factory.  I don't even think they have an oil pressure gauge standard do they? Most likely you have an oil pressure switch for a warning lamp which is not much use for logging.  

[JZJOE80]

9 minutes ago, Adamw said:

They dont have oil pressure or coolant pressure connected to the ecu from factory.  I don't even think they have an oil pressure gauge standard do they? Most likely you have an oil pressure switch for a warning lamp which is not much use for logging.  

yes correct no oil pressure gauge. i know for the water temp there’s 2 sensors one for the gauge and one for the ecu. 

would you recommend removing the factory oil pressure sensor and adding an after market one that the ecu can recognize?

 

[Adamw]

There is no factory oil pressure sensor.  Most likely it has a pressure switch for the warning light.  You will want to keep this for the light to warn the driver and add a pressure sensor, either by teeing into the same port or finding another. 

[JZJOE80]

10 minutes ago, Adamw said:

There is no factory oil pressure sensor.  Most likely it has a pressure switch for the warning light.  You will want to keep this for the light to warn the driver and add a pressure sensor, either by teeing into the same port or finding another. 

adam you’re a great human with useful knowledge! i thank you!!

[koracing]

Coolant pressure is nice to see if you're pushing combustion pressure into the coolant indicating a head gasket issue, so I assume that's why your tuner wants that as well as the coolant temp and the combination sensor is one of the easier ways to get both in one spot.  The OEM efi water temp (for ecu - 2 wire) will be fine and accurate for tuning otherwise if just coolant temp is not enough. 

For oil: I commonly install pressure sensors in place of the OEM switch and then run the switch wire to an ecu output that is triggered at a higher pressure point or if my oil pressure failsafe (GP RPM Limit 1 typically) is active.  The OEM switches dont' turn on until oil pressure drops below 4.3psi if memory serves me - which is too late in most situations.  A filter sandwich plate to add oil pressure and temp is also pretty common to use.  I actually installed one with the afore-mentioned sensor on a 2jzgte in the last couple days for a MK4 supra I'm retuning on an old Link G4+ Xtreme. 

The other sensor I would recommend if you don't already have one in your plans is a fuel pressure sensor and possibly a flex fuel sensor if you plan to run e85.

[Hodgdon Extreme]

Drilling/tapping the pipe plug in your oil filter housing adaptor is a nice way to implement a combined oil pressure + temperature sensor. You'll need to replace the OEM hex-key drive pipe plug with one that has an external square drive. This way, the OEM oil pressure switch can be left as-is; located in the center of the bolt that holds the oil filter adaptor onto the block.

For fuel pressure, I prefer drilling/tapping directly into the fuel rail.

For coolant temperature/pressure, you can either use the original ECT sensor location below the intake port for #1 cylinder, or you can leave the original ECT sensor as-is an use the plugged location that is about 50mm rearwards of the existing ECT sensor.

Here is a pic that kinda shows everything I wrote about above:

In this pic, you can see the combined oil pressure/temp sensor in the union bolt that holds the oil filter adaptor on. I removed the pipe plug from the oil filter adaptor and replaced with a 90* fitting to use for supplying oil to my turbo. In the head, you can see a brass pipe plug, plugging the rearward/secondary port into the cooling passage. The ECT sensor is a bit farther forward - you can just see the connector poking out between the VVTi banjo bolt and the oil filter adaptor.

[JZJOE80]

6 hours ago, Hodgdon Extreme said:

Drilling/tapping the pipe plug in your oil filter housing adaptor is a nice way to implement a combined oil pressure + temperature sensor. You'll need to replace the OEM hex-key drive pipe plug with one that has an external square drive. This way, the OEM oil pressure switch can be left as-is; located in the center of the bolt that holds the oil filter adaptor onto the block.

For fuel pressure, I prefer drilling/tapping directly into the fuel rail.

For coolant temperature/pressure, you can either use the original ECT sensor location below the intake port for #1 cylinder, or you can leave the original ECT sensor as-is an use the plugged location that is about 50mm rearwards of the existing ECT sensor.

Here is a pic that kinda shows everything I wrote about above:

In this pic, you can see the combined oil pressure/temp sensor in the union bolt that holds the oil filter adaptor on. I removed the pipe plug from the oil filter adaptor and replaced with a 90* fitting to use for supplying oil to my turbo. In the head, you can see a brass pipe plug, plugging the rearward/secondary port into the cooling passage. The ECT sensor is a bit farther forward - you can just see the connector poking out between the VVTi banjo bolt and the oil filter adaptor.

thanks for the response, would you recommend teeing at the fuel pressure regulator, for the fuel pressure?

 

also, https://www.driftmotion.com/AN-8-to-1-2-NPT-Fitting-p/dm1898.htm i was looking to go this route for the oil pressure, seems a lot more simple, and more accurate.

15 hours ago, koracing said:

Coolant pressure is nice to see if you're pushing combustion pressure into the coolant indicating a head gasket issue, so I assume that's why your tuner wants that as well as the coolant temp and the combination sensor is one of the easier ways to get both in one spot.  The OEM efi water temp (for ecu - 2 wire) will be fine and accurate for tuning otherwise if just coolant temp is not enough. 

For oil: I commonly install pressure sensors in place of the OEM switch and then run the switch wire to an ecu output that is triggered at a higher pressure point or if my oil pressure failsafe (GP RPM Limit 1 typically) is active.  The OEM switches dont' turn on until oil pressure drops below 4.3psi if memory serves me - which is too late in most situations.  A filter sandwich plate to add oil pressure and temp is also pretty common to use.  I actually installed one with the afore-mentioned sensor on a 2jzgte in the last couple days for a MK4 supra I'm retuning on an old Link G4+ Xtreme. 

The other sensor I would recommend if you don't already have one in your plans is a fuel pressure sensor and possibly a flex fuel sensor if you plan to run e85.

thank you extra for the response, I already have the flex fuel sensor installed. gonna reach out to my tuner and ensure that's what he meant since I ordered a temp sensor and not a pressure sensor.

[Hodgdon Extreme]

1 hour ago, JZJOE80 said:

thanks for the response, would you recommend teeing at the fuel pressure regulator, for the fuel pressure?

 

also, https://www.driftmotion.com/AN-8-to-1-2-NPT-Fitting-p/dm1898.htm i was looking to go this route for the oil pressure, seems a lot more simple, and more accurate.

Many fuel pressure regs have a pipe port where you can install a pressure transducer; or perhaps a hose that runs to a pressure transducer. That can work fine - in my case the sensor was too bulky to fit directly into the port. Instead, I drilled/tapped the fuel rail directly. An advantage to this compared to running a hose to a remote-mounted sensor, is you won't have an air bubble that damps/isolates pressure fluctuations. 

Regarding your URL to the 8AN fitting: I don't understand your vision for how that would be used. 

[JZJOE80]

10 hours ago, Hodgdon Extreme said:

Many fuel pressure regs have a pipe port where you can install a pressure transducer; or perhaps a hose that runs to a pressure transducer. That can work fine - in my case the sensor was too bulky to fit directly into the port. Instead, I drilled/tapped the fuel rail directly. An advantage to this compared to running a hose to a remote-mounted sensor, is you won't have an air bubble that damps/isolates pressure fluctuations. 

Regarding your URL to the 8AN fitting: I don't understand your vision for how that would be used. 

sent the wrong link, apologies. https://www.driftmotion.com/ProductDetails.asp?ProductCode=DM3904&CartID=1

 

this would be for the pressure sensor. 

 

correct i have a port under my FPR and was able to tee it there.

[Hodgdon Extreme]

39 minutes ago, JZJOE80 said:

sent the wrong link, apologies. https://www.driftmotion.com/ProductDetails.asp?ProductCode=DM3904&CartID=1

 

this would be for the pressure sensor. 

That'll work just fine. That particular port is already occupied on mine, because that's where Toyota chose to source the oil supply for VVTi.

To pic nits, however - I'm not in love with that Drift Motion adaptor if you will be using a combined oil pressure + temperature sensor, because there won't be any actual flow of oil over the sensor. It'll read pressure ok but there will be a bunch of lag in temperature readings.

[JZJOE80]

26 minutes ago, Hodgdon Extreme said:

That'll work just fine. That particular port is already occupied on mine, because that's where Toyota chose to source the oil supply for VVTi.

To pic nits, however - I'm not in love with that Drift Motion adaptor if you will be using a combined oil pressure + temperature sensor, because there won't be any actual flow of oil over the sensor. It'll read pressure ok but there will be a bunch of lag in temperature readings.

thank you so much