Justin Bieber — More Weed. More Problems.

Justin Bieber“s at the center of ANOTHER marijuana controversy — our sources has learned MORE photos of the singer holding a blunt are being shopped to media outlets.

The photos — which we”ve seen — show 18-year-old Justin and his bud Lil Za casually passing the weed-filled stogie back and forth while hanging outside of an L.A. home.

FYI — Lil Za is the guy who was pulled over and detained for driving Bieber”s Ferrari without a license early Friday morning. We”re told the marijuana photos were taken yesterday.

It”s not the first time Bieber”s been photographed with grass … just last month, Justin was pictured with another rapper — Lil Twist — holding a smoldering joint at a hotel party in Newport Beach.  Ironically, Bieber loaned the same Ferrari to Lil Twist January 1st.  You”ll recall a photog was struck and killed by another motorist while shooting pics of Twist being pulled over for speeding.

We reached out to Justin”s camp for comment … about smoking pot and loaning his car to less-than-responsible people.  So far no word back.