P0440 Chevrolet -

Question

Check engine light came on. The code is a P0440. A smoke test was done no leak was found the pressure held. the tech said the next option would be to start replacing parts. The gas cap is new so what should try next?

Answer 1

Hi there,

If there aren't any leaks, then usually the issue is the evap pressure sensor. This is what tells the computer there is a leak. If it's not working right, then the code would appear. Before throwing parts at it, have the pressure sensor tested.