mathewd23

Try resetting the P0440 code and take it for a highway driving and see if it comes back, i did that couple of time and it did not come back while highway driving but normally after i fill gas and while i am driving very less miles in the city say around 4o to 8 miles each day it comes back again. I have done the same thing of replacing the PCV , cleaning the MAF sensor and replacing the fuel cap, In fact i pulled the throttle body out this weekend to clean it up along with the air filter and all the hoses upto the intake manifold and placed it back, trying to see if i get the code again. I will keep everyone posted by the end of week to see if i get the P0440 code back again. Cheers.

jacknk

I found my problem. It was the L shaped rubber hose that goes to the air filter. It had a very small crack on the underside of the hose in the curve. You could not see it unless you removed the hose and then it was difficult to see.

mathewd23

wow, thanks for the update, as i too get the same P0440 error code sometimes like "Emissions System Malfunction" I will see if have the leak on the same hose too.

jacknk

It is the emission hose that goes to the back of the air filter. The same one that get pulled off is the filter is changed or checked.