Did you use a OEM front O2 sensor. If not, do that next time. Trust me again. the rear O2 can be after market...so far mine is good, but I had to replace the 2 year front with a OEM one last month.
Same with Hubs, front should be OEM, rears can be Moog
211,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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