po445 code on 2007 gmc sierra 4.3 v6

Question

I have already changed fuel caps with a new cap,what are other causes of po445 code?

Answer 1

Hi there,

If replacing the fuel cap doesn't resolve the issue then the next step is a smoke test. The test basically fills the evap system with smoke, then a very powerful light is used to find the leak. Since we are talking about a leak of .5 mm or less, this is the best method for locating the leak. Once the leak is found, you can then do the repair yourself to save some money.