Like title states I have a 1996 sc300 in California that won’t pass smog and I just realized that someone cut the egr temperature sensor . I can see the wires cut but I don’t know what plug they should connect to if anyone could upload a picture or tell where to look I would greatly appreciate it I tried searching all over google .

 

That sucks, Brainzz

The EGR temp sensor screws into your EGR valve and its connector goes into a mating connector located on the engine harness. Hopefully the previous owner didn't cut that off too.

If they did then we'd need to get your the engine harness side EGR connector part number and its two OEM terminal wires so that you could repair that connection and get your sensor talking to the ECU again.

The two wires that go into that EGR connector go right into the main engine ECU all the way through the wiring harness down into one of the big ECU connectors in the passenger footwell.

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I would recommend going on to RockAuto, typing in your 1996 Lexus SC300 criteria and buy one of their Ultra-Power ETS6 EGR temperature sensors under "Exhaust & Emission > Exhaust Gas Temperature (EGT) Sensor" to have a new one ready to go in.

Alternatively, IF your existing EGT Temp sensor tests good according to the TSRM procedure (you can test this with the vehicle warming up from full cold with a multimeter connected to both wires on the sensor side so as to note the electrical resistance range as as specified by Toyota) then you could do some wire repair on that one with an old/bad EGR sensor connector to save it and keep it going until it wears out.

But if the engine harness side EGR connector has been cut off that will need to be restored. First you'll need to find the wires for it if that is the case. Hopefully not.

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This may be overkill but just in case it may help you out since you're trying to pass CA smog, in this troubleshooting thread I made a few years back you will find every aspect of what I did to overhaul the entire SC300 EGR system, ignition system, catalytic convertors and ECU (new capacitors) in order to finally pass CA smog with my original stock engine. My car is a CA Emission Spec 1993 SC300 but all of the same procedures will apply to your 1996 CA Emission Spec SC300 other than your ECU being different and the EGR temp sensor type being a different part number for your model year.

Notably I covered something that even the Lexus SC300 TSRM doesn't cover: how to clean your intake manifold Y-pipe's EGR passages. These can become clogged over many years and require a full cleaning out before you can get proper EGR gas flow again to satisfy the EGR valve, EGR vacuum modulator and EGR temp sensor within the flow range that the ECU wants to see.

The original "mystery" issue that I had been chasing in that thread later turned out to be excessive carbon buildup over time which caused an eventual head gasket issue but you can ignore that and just focus on all the notes with the EGR system (and overall emission system). That is, IF it can help you beyond your current issue with the EGR Temp Sensor.

https://www.clublexus.com/forums/per...ly-solved.html

And in case you need it, here are the two threads that I made on the 19921-997 2JZ-GE upper intake manifold "Y" cleaning procedure which can sometimes be needed to get the EGR flowing correctly again:

https://www.clublexus.com/forums/per...-cleaning.html
https://www.clublexus.com/forums/per...manifolds.html