Checked mine today, the cap wiggles after filling the tank.
The threads feel tight and the seal feels tight, but the plastic cap has play.
178,000+ miles, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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