Took me forever to find it, middle rear just in front of a heater hose and right side fuel rail hampers getting a hold of connector to remove it. Anyhow, not sure why the instructions for this is so little, maybe I am just not a good enough sleuth.
Cold motor.
Drain some coolant about 3/4 to one gallon,
radiator drain is at bottom left, open till small amount drips, remove cap, adjust as necessary.
so you don't have it leaking all over when replacing temp sensor.
Remove air filter and
next intake air housing up to throttle body, including throttle body clamp,
the 2 10mm screws,
the connector to Mass Air Flow Sensor, and
1 vacuum line at rear of housing.
then 3 bolts for the passenger side fuel rail, real tight, (not sure of the torque, I just tightened approximately as tight as I thought when they came off without stripping, but they are tight).
no I didn't disconnect the fuel line or relieve the pressure,
just lifted the fuel rail up high and forward enough to get my hand in to disconnect the sensor, you'd better have fairly small hands or your results may very and you will need to do more.
And yes, all three injectors are lifted as is within the rail for the duration, be careful!
Or if you could figure out how to disconnect the sensor connector and get it off with pliers, screwdriver, ect, then you could get around lifting the fuel rail forward.
Squeeze hand into the tight space to disconnect temp sensor.
Then its easy
19mm socket removes old sensor,
install new sensor,
connect the plug,
3 bolts to fuel rail, be careful placing injectors correctly
install air housing not forgetting the vacuum line at rear
before connecting the electrical connection--clean Mass Air Flow sensor that is located at front top of housing, 2 Phillips screws (remove, spray up into to clean the 2 resistors inside the bottom, the little bulb is air temp I think, but be sure you know where the resistors are and get them cleaned too).
reinstall and connect Mass Air Flow,
button up the air filter.
Here's the only reference I found prior to changing it out;
| Repair Guides | Coolant Temperature Sensor | Removal & Installation | AutoZone.com Although I found some other instructions I'll link to that later if I can find it, probably from the Tacoma forums.
I also might have disconnected a tie-down(plastic rivet or whatever they call it) for wire harness nearby, but it seems this may or may not be necessary.