1999 Chevrolet Blazer Q&A

1999 Chevrolet Blazer Question: what problem would give me a oem code of PO440 on my chevy blazer?

what would most likely be the problem and what order of troubleshooting should i follow? -
Answer 1
EVAP CONTROL ISSUE. SEEK A DIAG THESE PROBLEMS CAN BE A HAIR PULLING ISSUE EVEN FOR US -