Flushing the compressor manifold or the compressor itself?
If the later, never!! Remove compressor and turn by hand.

If your 300TE is R134a, take the opportunity, remove compressor hand turn it clean using new oil, replace receiver/drier, flush all lines minus expansion valve then fill with R12 and enjoy a much colder system. (and longer lasting compressor)

Regardless, you need to replace receiver/drier either way.

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2016 Monsoon Gray Audi Allroad - 21k
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