There may be a whistle or squeak sound heard coming from the engine area on some 2019-2020 Blazer models equipped with the 3.6L 6-cylinder engine (RPO LGX). The sound may be more noticeable after driving the vehicle for a while.
The sound may be caused by plastic flashing restricting the clean air port on the air cleaner duct on top of the engine. (Fig. 38)
Fig. 38
It will appear that the restriction or flashing is partially blocking the hole inside the air tube, about 2 inches (5 cm) inside the tube. (Fig. 39)
Fig. 39
To correct the condition, replace the air cleaner duct. After installing the new air cleaner duct, run the engine long enough to build up crankcase pressure and check for any noise conditions.
– Thanks to Aron Wilson
