i had a poping noise in my 300d t and all it was, was the air cleaner had come unmounted (i still havent fixed it, but you can set it back in place for a temp fix)

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83' 300D Turbo ~ 168k (process of getting a new engine)
90' 300TE ~ (SOLD)
81' 240D (SOLD)
84' BMW 318i (SOLD)
91' BMW 318i ~ 120k
88' BMW 325i (SOLD)