"And people said you knew nothing about cars," Musk's mother wrote in a tweet, hashtagging it "1995" and "Found This Photo".
Tesla and SpaceX CEO noted that he could not afford to pay for a mechanic to fix his car, so he did it himself with junkyard parts.
"Could not afford to pay for repairs, so I fixed almost everything on that car from parts in the junkyard. Ironically, that's me replacing broken side window glass. The circle is complete lol," Musk replied on Wednesday.
Musk said that he was repairing the window because thieves had broken in and stolen the radio, which was worth maybe $20.
"Yeah, 1978 320i that I bought in 1993 for $1400. I hotrodded it by jamming in a 5 speed transmission from a later model I found in a Philly junkyard when the 4 speed transmission failed," he added.
Recently, taking on the pickup truck market leader Ford, Tesla CEO Elon Musk unveiled the ambitious six-seater electric "Cybertruck" at a packed house here that will soon be seen on the roads.
Starting at $39,900, "Cybertruck" is inspired by "Lotus Esprit S1" from the Bond film "The Spy Who Loved Me".
The truck will come in three versions with 250 miles, 300 miles and 500 miles of range, respectively.
( With inputs from IANS )