Keep getting P0440 code

So your thinking its just the gas cap? Even though I have already had 2 smoke test done? That would b great, considering I have already spent $350 in repairs in 2 weeks all for the light to come bck on. :(

Fixed several with just a simpe fractory gas cap replacement! Fixed one for a customer that had spent 500.+/ with a gas cap!! This is just a guess but one to consider. This was an Impala 2002. Smoke test can be very effective IF at that time failure is present!!

I will try that thank u, wish me luck ;-)

You got it!