05 Subaru Forester 02 sensor/fuel trim problem

05 forester,replaced 7 02 sensors in 5 years ,and the ECM all under warranty, now another blown sensor with fuel trim / idling problem…Dealer won’t service due to warranty expired…car excellently maintained…local repair guy handles only subarus…he is puzzled…help??

Dealer will service the car, you just have to pay for it.
Also, you could write a letter to Subaru of America, and tell them that your car has had a long history of killing O2 sensors and ecu’s, and that your car has had yet another failure.

Also, if the ecu goes bad in the near future, that should be covered under the Emissions Warranty. Look in your owners manual and see how long that is for your car.


It would be nice to know what the condition of the sensor failure was. If they all were the same thing. I assume there was just no output. How is the coolant level holding up over time? If you have to add coolant every so often then that may be the cause as the antifreeze will damage the sensor over time.