Hi guys,

I just replaced 2 main O2 sensors on my 93 SC400 with universals O2 sensors made by Denso, I bought them from sparkplugs.com for $45 each. My car has 114,000 original miles, no trouble codes, just thought it was time to replace them as preventive maintenance. Pretty easy to do, but a PITA to get to, here are the steps:

1. Drive car on ramps, position jack stands for additional safety and chock rear wheels.

2. Disconnect and remove original sensors (they are located right above the rear bushing of the lower control arm). Access is very thight, you'll need an offset flare-nut style O2 socket ($10 at Pep Boys), 10" long 3/8" extension bar, and a breaker bar. Don't even try to use a regular wrench, not enough room and you will round the corners off the sensor.

3. Once the sensors are out, just follow the directions that come with the new universal O2 sensors to splice the orignial connector onto the new sensor. All supplies are included such as crimp connectors, heat shrink tubing, and anti-seize compound.

4. The original sensors had Toyota stamped on them, but I'm pretty sure they are made by Denso, the wire colors are identical. Two black wires for the heater, blue signal wire, and a white ground wire. Just match them up, you can't go wrong.

5. Once you have the connector spliced in, coat the threads with anti-seize then re-install. Torques value is 33 ft-lbs.

6. Disconnect the 30A EFI fuse for 1 minute to reset ECU, are you are all set to drive.

I did notice better throttle response from the engine and might even get better MPG, will report back in a couple of tank fulls.

DJL

 

Although 2 years old, great write up.
Will do this before winter comes.

 

...have you had enough tank fulls by now to report back?

 

2 years of trouble-free service from these universal O2 sensors, can't beat them for the price. I'm consistently getting 23 to 24 MPG on highway, the car now has 142,000 miles.

djl