Did you check the heater connections. The Hoses and all that goeas to the firewall. Do you get antifreeze inside car?

Have you tried to diagnose this? Compression check, leakdown tests?

I too have a feeling you have begining of chain slap. But check the oil ASAP just in case.

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2006 4.8is, Black on White. SOLD Sniff Sniff.

2017 F85 x5m, Black on Red. BEAST MODE


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