2002 Buick Century V-6 3.1

Question

PO440 code changed gas cap & purge valve w solonoid. Disconn & reconn batt cables service eng ljght stayed on. Can't pass smog ck. What should be my next step & next 2 steps after that. Pls help

Answer 1

Hi there

There are a lot of different possible causes for this code. It could be simple like a gas cap or more complex like a problem with the fuel tank pressure sensor. Here is list of possible cases and things you should check.

P0440 BUICK - Evaporative Emission System

Read more: https://www.autocodes.com/p0440_buick.html