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Hi, this has probably been asked about a million times.
I'm a relatively new corvette owner, yesterday i got a check engine light, scan the codes P2120 H C, and P0442. From what i can find on different posts these two codes can both give a check engine light.
For P0442, I've inspected the purge valve and the solenoid and it atleast looks to be alright, then i went to look in the gas cap, and i can see damage on the rubber, is this enough to get a check engine light?
And for P2120 H C, where should i start looking? I struggle to find any information about this particular fault code, atleast for C5 corvettes. Thanks in advance
Hi, this has probably been asked about a million times.
I'm a relatively new corvette owner, yesterday i got a check engine light, scan the codes P2120 H C, and P0442. From what i can find on different posts these two codes can both give a check engine light.
For P0442, I've inspected the purge valve and the solenoid and it atleast looks to be alright, then i went to look in the gas cap, and i can see damage on the rubber, is this enough to get a check engine light?
And for P2120 H C, where should i start looking? I struggle to find any information about this particular fault code, atleast for C5 corvettes. Thanks in advance
Yes, a bad or loose fuel cap on a C5 Corvette (1997–2004) can definitely trigger a Check Engine Light (CEL) and create specific codes. Because the fuel system is sealed and pressurized, a poor seal at the gas cap allows fumes to escape, causing the EVAP (Evaporative Emission) system to detect a leak. [1, 2, 3, 4]
Last edited by helga203; May 22, 2026 at 11:07 AM.
Hi, this has probably been asked about a million times.
I'm a relatively new corvette owner, yesterday i got a check engine light, scan the codes P2120 H C, and P0442. From what i can find on different posts these two codes can both give a check engine light.
For P0442, I've inspected the purge valve and the solenoid and it atleast looks to be alright, then i went to look in the gas cap, and i can see damage on the rubber, is this enough to get a check engine light?
And for P2120 H C, where should i start looking? I struggle to find any information about this particular fault code, atleast for C5 corvettes. Thanks in advance
What is a P2120 on your 2000 ??...you can't diagnose by it "looks" ok...if you don't have a factory level scan tool you can just replace the gas cap to see if that "small leak" DTC goes away.
P0442 and P2120
