error codes 32 and 34,

[jesusgonzalez7]

Hello, i've had de cel on for about 5 months, i ran the autodiagnosis and pulled de error codes 32 and 34, which are knock sensor and egr system, but one week ago the light turned off by itsel, does this mean that the problem it's fix,???

my doubt is what does it men that the cel turnes off by itself?

P.D. my mpg improved like 10% since the light went off,

thank you...