Hi sir. Have a Little problem with the upstream o2 sensor. I’ve been chasing gremlins in this car. Its an 02 subaru wrx wagon. I know what you’re gonna say. Subaru piece of junk. I agree on some of them, but this car drove kinda fine. Up till about a month ago. I’ve had it for about almost a year, but it’s been running kind of rich ever since I bought it . It started eating up gas so I checked the spark plugs and they were gapped all the way up to 40 which seems a little wide to me. I bought new plugs and got them at 28 says from factory That fix the misfire code I was having but then the O2 sensor went out and gave me a code p0031, ho2s heatercontrol circut low bank one sensor 1. So now I bought an O2 sensor and I admit I bought the cheapest one I could find which could’ve been a mistake and now it’s showing a code p1130, unknown diagnostic trouble. I tested the original O2 sensor that was in the car or the ohms meter is show it read nothing. The cheap O2 sensor I bought I tested. It shows one which seems low too. Could it be that the O2 sensor is just a piece of junk should I pay 200 or more dollars for the OEM one?I just need to know what direction I should head before I spend a butt load of money. By the way, the car is straight, piped the owners before took the cat out.
I know what you’re gonna say. Subaru piece of junk.
Not quite. A 2002 Subaru was not a bad car 22 years ago. The most common problem with those older models today is blown head gaskets, but if yours is a WRX turbo better gaskets were used that are not as trouble-prone. Of course an old Subaru is also susceptible to the same kinds of issues that any vehicle is likely to develop when its age is measured in decades.
I bought an O2 sensor and I admit I bought the cheapest one I could find which could’ve been a mistake
Not "could've been" - it was a mistake. I've been down that road myself and found out the hard way that it's best to use OEM sensors, or at least sensors made by the original supplier. (Bosch in my case. For Subaru it's probably Denso or NTK.) By saving a few bucks I wound up with all kinds of spurious codes that were driving me nuts. They all went away when the correct O2 sensor was installed.
Of course it can't be guaranteed that you'll have the same experience that I did.
By the way, the car is straight, piped the owners before took the cat out.
This means you'll always have a check engine light and catalytic converter codes, but if you're in a state that doesn't do emission inspection you don't have to worry about that.
