knock / rattle
knock / rattle hey guys attached is a vid of my engine. When I rev to 1200 to 2000 rpms there is a rattle. I can't tell for sure if it is the top end or the bottom. It seems to make the same exact noise when the car is at idle when cold so I though it was piston slap but since it does it when it is up to temp at the rpms stated above i though it might be the infamous valve train noise that I i have seen mentioned. It will not make the noise when the engine is under a load....only happens when held at that rpm or on the way back down from a rev. I've had a dealer look at it before since it had extended warranty left on it but they told me it was normal for this engine, but the guy could not tell what it was.
Let me know what you think
thanks much
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<br><br>Click
here to see Video
Let me know what you think
thanks much
<br>
<br><br>Click here to see Video
TECH Addict
Joined: Dec 2001
Posts: 2,907
Likes: 1
From: Bergen County, NJ
Sure sounds like valve train but strange that it doesn't do it under load. I would try two things as a first step - remove the AIR tubes from both sides, and block off the ports with a metal plate - easy enough to make from some metal, snips and a drill. Then try removing the belts. The check valves in the AIR tubes can bounce and sound like that and belts and pulleys can do some really strange things.
If it's neither of those, pull the valve covers and check the rockers and push rods.
Also, the engine looks stock but give us details, any mods, mileage etc.
If it's neither of those, pull the valve covers and check the rockers and push rods.
Also, the engine looks stock but give us details, any mods, mileage etc.
Check and see if its an exhaust bolt. My buddy had a loose header bolt, buit before we figured that out we took both valve covers off of his LS1 and checked all the pushrods, took us 3 hours till we noticed a loose header bolt rattling around, took him roughly 15seconds to fix the actual problem after 3 hours of wasted time 
thanks for the input guys. The car is 2002 M6 with 26,000 miles. i bought it new. The engine is completely stock. The car has only been driven about a 1000 mile per year for the las two years. I started to notice this noise last year and this year. I think it did it before but not nearly as loud. I don't think its a bent push rod since I cannot remember ever missing a shift that bad.
Anyway I'm picking the car up from the dealer in a few. Getting the water pump replaced(extended warranty). So far the service advisor said he thought it was normal but would have a tech listen to it.
I'll post back later.
thanks
Anyway I'm picking the car up from the dealer in a few. Getting the water pump replaced(extended warranty). So far the service advisor said he thought it was normal but would have a tech listen to it.
I'll post back later.
thanks
Just got back from the dealer. They had two mechanics look at it. They both said the it is normal for and LS1 to make this noise, that it is mostly valve train noise. The service advisor also mentioned there was another ls1 that just left(it was in for the antenna) that made the same exact noise at the same rpms or when the rpms were coming down.
Since the car is running like a champ, not using any oil, and seems to have no power loss I think I'm going to call it good, at least for now unless you guys think other wise.
Also since I'm getting ready to park it for the winter should I change the oil? It has M1 with a K&N filter that is about 6 months old and a little 1000 miles.
Previous winter I have changed it before I parked it and then again when I pulled it out in the spring. I just don't know if this is really needed or not.
Thanks
Since the car is running like a champ, not using any oil, and seems to have no power loss I think I'm going to call it good, at least for now unless you guys think other wise.
Also since I'm getting ready to park it for the winter should I change the oil? It has M1 with a K&N filter that is about 6 months old and a little 1000 miles.
Previous winter I have changed it before I parked it and then again when I pulled it out in the spring. I just don't know if this is really needed or not.
Thanks
