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Brand new AT4 engine knock

2K views 9 replies 4 participants last post by  MrMcCroder 
#1 ·
So… we literally drove this home from the dealership on Tuesday, then to grab dessert on Wednesday, and today, while sitting and setting up my driver profile this happened… the car had been idling for about 15 minutes totally normal and out of nowhere. Has anyone had this happen?!? Already called the dealership, hoping they really make this worth while to keep it!

Standby while I figure out how to post a video, sounds like rod knock to me but goes away around 1200-1500 rpm
 
#3 · (Edited)
Sounds like the noise is high in the engine, so probably not a rod knock. Could be something worked by a camshaft is starved for oil (valve lifter, rocker arm, etc.). Did you check the oil level?
 
#5 ·
Does not sound like a rod knock. As the camera moves away, it almost sounds like a bad idler pulley.

That's why vehicles come with a warranty. Parts do fail out of the box. Back when my wife bought her '14 Forester, the HVAC fan failed the first week she had it.

Not sure what the OP means by hoping the dealer makes it worth while to keep.
 
#7 ·
... As the camera moves away, it almost sounds like a bad idler pulley.
Interesting guess - and possible. Might even be a bad pulley on the belt tensioner. Would be a plus if either was the case (no engine tear down required ;)).
 
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