Here’s the rundown:
- Engine Oil – Mobil 1 5W-30 (5 Quarts) + Mobil 1 M1-108
- Transmission Fluid – 12 Quarts Subaru ATF-HP
- Differential Oil – Mobil 1 75W-90 (2 Quarts)
- MAF Cleaning
- Front and Rear O2 Sensors
- Front: Denso 234-9123
- Rear: Denso 234-4445
- Air Filter – Purolator PureONE PA24278
- PCV Valve – Autozone PCV1013
- Exhaust Gasket (Cat-to-mid pipe) – Bosal 256-1112
Next was the PCV valve. I hadn’t done one before, but I removed all the air box and was able to get to the line attached to the PCV valve. Removed the line, swapped it out, easy peasy. Honestly, not even sure if there is a benefit, but one of the NASIOC threads I used for gathering supplies replaced it, and it was all of ~$10 to swap.
Here’s pre and post PCV valve:
Next was the exhaust gasket; this was not a regular maintenance item. Instead, the last time I had the exhaust off, I noticed that the gasket between the catpipe and the midpipe was ugly as all get out:
Here’s a side-by-side of the old as I was scraping it off, and what the new looks like:
And after much scraping and sanding off the rust, finally got the new one on:
I then went to pull my O2 sensors, as I was getting a check engine light about the air-fuel ratio. Turns out the front O2 sensor was completely cross-threaded , and had actually melted part of the threads of the sensor into the threads of the exhaust.
I cleaned out as much as I could and made sure that the new one went into the threads as much as possible, but I’m not confident about it. Here’s the old vs. new, rear to the left, front on the right:
I did see smoke coming from the front O2 sensor so I’m thinking that the light is going to come back on eventually. I’m not sure if there is a leak and I’m seeing exhaust or if the sensor is melting again. I’ll probably start looking around for a used header setup from an ’06-’08 in the hopes that a simple swap will solve my problems. Either way, it was nice to get back to work on the wagon.
For reference: NASIOC Thread I used to compile parts, etc: DIY: 30k Maintenance for Naturally Aspirated Imprezas – NASIOC