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Japan, Tokyo
1 Level
745 Review
51 Karma

Review on Enhanced Denso 234-9120 Air-Fuel Ratio Oxygen Sensor by Brad Arthur

Revainrating 5 out of 5

Good fit for FRONT Heated O2 Sensor

I bought this to repair P1153 "O2 Sensor Circuit Range/Performance (High) (Bank1 Sensor1)". Check the engine light code on a 2005 Subaru Outback XT. I interpreted this as a front O2 sensor voltage reading staying high. The engine has done 121,000 miles and has been running on 3 cylinders for the last few thousand miles so I wasn't surprised that it destroyed the O2 sensor. This Denso 234-9120 part came with a connector that plugs directly into the engine wiring harness connector. . The silicone case was blue compared to the yellow of the original sensor. It even came with two snap-on cable ties that fit into the bracket on the ignition coil. There was only a small problem because the zip tie points were pushed back about 10mm from the original, but it was easy enough to push them up a bit by hand. The package also included a small tube of anti-seize copper paste - enough for at least 10 O2 sensors, so I'll take it the next time I need to work on the exhaust system nuts and bolts. It was surprisingly easy. To get to the O2 sensor on the exhaust manifold it needs to be the same as on the WRX or Legacy GT. I simply turned the front wheels all the way to the right, removed a plastic clip for the front underbody pan in the wheel well and removed the old O2 sensor with 3 long extensions on the O2 sensor socket. I didn't have to remove the wheel or jack up the car using this method. Before replacing the O2 sensor, my OBDII scanner showed that the rear (unheated) O2 sensor voltage reading was stuck at around 0.8V. But after replacing both O2 sensors (due to the age and mileage of the vehicle) I see while driving it goes from 0.2v to 0.7v. The best part is that there is no Check Engine light more, so I can finally inspect the car.

Pros
  • Sequins
Cons
  • Upgradeable