[Samirr76]

This is our fourth Subaru. So far, 1993 Legacy Turbo, 2002 WRX, 2003 Baja, and now 2009 Outback 2.5i with the 5 speed Manual.

at highway speeds sometimes I hear a high speed engine knock. I dont hear it at idle and I dont hear it driving around town. Mostly I would say around 3,000 roms, cruising about 60-70mph. t seems like the baja's 2.5NA engine is much quieter than our 2009 Outback.

If its normal I dont care. I jsut want to know. Otherwise we love everything about it.

 

[ScoobyRu]

Engine knock? Nope. More than likely it's a loose heat shield. Mine does the same thing when I hit 3k rpm. One day I'll fix it.

 

[mrk610]

I had a knock type sound also on the highway. I mainly heard it coming from the pass side ofthe car.
Got underneath and noticed the long heat shield that covers the middle u joint and shift linkage from the exhaust was broken off of 2 bolts.
Might be your noise might not be.

 

[Samirr76]

Well the dealer replaced some heat shields at no cost to me, I knew they were making noise, but that was not the noise I originally posted about here. The heat shield noise is gone but I still hear that piston-slap type noise at highway speeds at part throttle. If I let off it goes away, if I get on it hard it goes away. It almost is a diesel engine like sound.

The dealer told me its normal for this generation. I just wanted to be sure.