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As mentioned in this forum, I changed the gas cap with an AC Delco one and cleared the code. About 50 miles later code came back so it’s not that. Thoughts?
 

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That P0442 is seeing a small EVAP leak condition. I guess a gas cap could be the cause of a small leak, but I think it almost always is the cause of a large leak condition, creating a P0455 code. The car monitors the fuel tank pressure after engine shut down. If it detects a greater pressure loss (within a specified time period), it will set that P0442 code. The system "has" to fail on 2 consecutive run cycles before it will set that code. Assuming that the fuel tank pressure sensor is OK, it reads like something is wrong with the EVAP plumbing. It goes from the intake manifold, thru the purge valve, back to the EVAP canister, an then to the tank. If the canister vent valve or the purge valve do not shutoff to seal the system (when thay are told to do so), your pretty much going to fail that "after engine shutdown" pressure test.
 

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What color is the lettering on the new gas cap? Is the plastic tether on the gas cap attached to the vehicle? essentially, the check code represents an evaporative emission system leak.
 
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