5.3 start up knock
#1
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5.3 start up knock
Hey guys, I am trying to find out what is causing this embarrassing knocking when I cold start my motor. It is a 5.3 with ls6 cam and intake, milled heads, and longtubes. It doesn't always happen, sometimes it'll knock once or twice, other times it knocks like in the video. Any ideas on what it could be? It goes away when it revs, and gets hot. It doesn't do it on a hot start.
#2
Hey guys, I am trying to find out what is causing this embarrassing knocking when I cold start my motor. It is a 5.3 with ls6 cam and intake, milled heads, and longtubes. It doesn't always happen, sometimes it'll knock once or twice, other times it knocks like in the video. Any ideas on what it could be? It goes away when it revs, and gets hot. It doesn't do it on a hot start. http://youtu.be/Hjm3vOWjWI4
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It sounds like a very solid knock, not like I imagine from a lifter. It has brand new ls7 lifters. I'm thinking it might be the long tubes rattling against something in the bay when the motor rocks real bad. It's got stock rubber mounts. Sometimes the idle drops and bounces near 300rpm and back to 500 and the motor with rock and knock. Only on cold start up
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It reminds me of the sound it made a while ago when the torque converter bolts backed out. But those got faster when revved and never went away. I've already checked them. It's coming from the back of the motor ish.
#7
Whats your exhaust set up?
I run longtubes, 3.5" y and 4" to a single muflex dumped. Use to not make any noise. No with the cam the exhaust rocks so much on cold starts, It sounds like my muffler smacks the floor board, but it's tight as can be. Def my exhaust though, just a thought. That doesn't sound engine related though.
I run longtubes, 3.5" y and 4" to a single muflex dumped. Use to not make any noise. No with the cam the exhaust rocks so much on cold starts, It sounds like my muffler smacks the floor board, but it's tight as can be. Def my exhaust though, just a thought. That doesn't sound engine related though.
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It's pacesetter longtubes, tsp ory, and 3" to the muffler. I know the pipe hits over the axle when driving but not idling. I think it might be hitting the steering shaft on the drivers side