Check Engine Light Due to Gas Cap Issue on Chevrolet Impala

Problem Description and Possible Solution

A Loose or worn gas cap may cause Check Engine Light to illuminate.

Problem Data
RepairPal Verified
Average mileage: 90,705 (23,000–200,000)
12 model years affected: 2002, 2003, 2004, 2005, more2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
163 people reported this problem
Viewing 1 - 20 of 63 comments
I kept getting the check engine light and tighten gas cap. Paid dealership (almost $200 including labor) for a new gas cap. Now almost a year later getting same check engine light and tighten gas cap. This time they're saying I need to replace evap vent solenoid for $130. It seems like a lot of the issues with this car are the same. GM should step up and solve them.
Check engine light is on. It says check gas cap, However gas cap is tight.
Check engine light illuminated due to gas cap issue. Replaced cap. Check engine light still on
reports gas cap, replaced but keeps repeating. paying 100 dollars each time for poor service. weather, raining it comes back. Three gas caps later it still comes back? Help.
Engine light comes on, reads large emissions leak, replaced gas cap.
loose gas cap keeps causing check engine light
Replaced gas cap; still have problem.
Clean off the inside of the gas cap with WD40. After I got all of this dirt out, the "Tighten Gas Cap" error never came back up. Air must have been getting into the system and reducing the vacuum pressure for the gas going to the engine.
Not fixed. Per code it my gas cap. Replaced it but problem continues. Normally I wouldn't care but because of this I cannot use my auto start
Same issue, worn gas cap allowing air in the tank and check engine light. Bought a new cap and fixed the issue. 50,000 miles later still no re-occurrence.
3rd time in 7 months the check engine light came on and dealer keeps telling me the gas cap isn't on tight enough. i'm soooo sorry i bought this car!
engine light came one whenever I got gas, replaced cap and it was fine for two years, now it has started again.
check engine light came on due to faulty gas cap.
stopped to refuel, took off from gas station and the check engine light came on ....the gas cap does not want to set in place and is loose. where can I get a new cap?
have replaced the gas cap 3 x at different intervals so far.
Same issue, same story, paid for the most expensive gas cap they could find!
engine light came on . we took the car to have it checked and were told the gas cap was faulty! REALLY?
had to buy a gas cap from chevy dealership because of tighten gas cap indication
engine light on; replaced gascap...one of many issues with this car...
Engine light on from gas cap. Tighten cap, it will go off after a few weeks. But come on again periodically