I have a 2005 forester X, completely stock engine. I threw a few codes awhile back that had to do, I thought, with the front O2 fuel mixture sensor. The codes were PO131 (O2 sensor circuit low voltage) and POO31 (HO2S heater control circuit low). The car was running just fine, but I was getting terrible fuel economy. I ordered a brand new front sensor, and I installed it a couple days ago and cleared the codes.
The codes stayed away for about a day, and then I got another CEL. Reader showed confirmed P1153 (no extra info), pending P2096 (Post catalyst fuel trim system too lean), and P0420 (Catalyst system efficiency below threshold). I have had the P0420 before, and I've read that its not a big deal, but I've never seen these other codes. At this point the car was running just fine still, but once again, the fuel economy was garbage.
Later the same day the codes came up, I went out to start my car. I live in a pretty cold environment (it was about -17C, 1.4F). The first time the car started up fine, but the idle dropped down right away and died. The second time the idle was surging, and barely staying alive. so the third time I blipped the trottle after it started and it idled fine. Then, as I was driving home, the engine has terrible power and would surge and stutter around 2000rpm. The car could barely hit highway speed, and could not climb hills without dropping at least one gear. The engine codes are still the same as before. Even after sitting in the garage for a night, the idle still surges.
Now I am at a loss and do not know what to do. I cleaned the MAF, and checked for vacuum leaks, as I read these are possible culprits.
Is my new sensor a dud?
Thanks in advance for the help!
The codes stayed away for about a day, and then I got another CEL. Reader showed confirmed P1153 (no extra info), pending P2096 (Post catalyst fuel trim system too lean), and P0420 (Catalyst system efficiency below threshold). I have had the P0420 before, and I've read that its not a big deal, but I've never seen these other codes. At this point the car was running just fine still, but once again, the fuel economy was garbage.
Later the same day the codes came up, I went out to start my car. I live in a pretty cold environment (it was about -17C, 1.4F). The first time the car started up fine, but the idle dropped down right away and died. The second time the idle was surging, and barely staying alive. so the third time I blipped the trottle after it started and it idled fine. Then, as I was driving home, the engine has terrible power and would surge and stutter around 2000rpm. The car could barely hit highway speed, and could not climb hills without dropping at least one gear. The engine codes are still the same as before. Even after sitting in the garage for a night, the idle still surges.
Now I am at a loss and do not know what to do. I cleaned the MAF, and checked for vacuum leaks, as I read these are possible culprits.
Is my new sensor a dud?
Thanks in advance for the help!