Whistling sound engine compartment
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Joined: Jul 2003
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From: North Scottsdale, AZ
'71 Pinto
Whistling sound engine compartment
DTB S-B-01.20/24 FEB09 ML63, C63, CLK63, E63, CL63, CLS63, S63, SL63, and R63 up to engine # 156698x 60 022000 - whistling sound from the engine compartment (in the area of the firewall) the cause may be a malfunctioning diaphragm in the pressure-regulating valve. The sound can also be heard for up to several seconds after the engine is switched off. The sound goes away when the engine dipstick is removed. To resolve, the valve is replaced.
