Cold start up knock?
Cold start up knock?
Hello I have done some reading about these motors as far as idle time etc. My question is the knock that happens on cold start and then goes away quickly. Other early LS1 car I have owned you could here lifter noise but then it would go away. I know these motors part of the problem is the AFM or DOD. I could have that tuned out but if i hear this knock is it too late? Anyone just going with it and driving their car until something happens? Please let me know. Any help is appreciated
2011 Caprice PPV
2012 Impala 9c1
2008 Cobalt SS Turbo
2008 Suburban
2012 Impala 9c1
2008 Cobalt SS Turbo
2008 Suburban
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- Location: Tampa, FL
Re: Cold start up knock?
I'm not saying it is your AFM lifter(s) but if it is, it may be because the internal lock is not engaging for whatever reason and it is in its "collapsed" configuration at startup. Once its respective cam lobe bumps it a few times it re-locks and the lifter goes into the "un-collapsed" condition. Whether the lifter is clogged preventing the lock from actuating or the spring loaded lock is failing, it will get worse eventually. When is the question.
Again, IF it is the lifter, it should be replaced. That's my 2 cents.
Again, IF it is the lifter, it should be replaced. That's my 2 cents.
2014 Chevrolet Caprice PPV
2014 Chevrolet Stingray Z51
2016 AMG C63
2015 BMW X5 iDrive 50i
2014 Chevrolet Stingray Z51
2016 AMG C63
2015 BMW X5 iDrive 50i
Re: Cold start up knock?
Thanks for the reply. I changed the oil to a heavier weight. I think for the most part it went away soonat. I experienced something similar on my old 09 Impala SS when the cam was completely destroyed
2011 Caprice PPV
2012 Impala 9c1
2008 Cobalt SS Turbo
2008 Suburban
2012 Impala 9c1
2008 Cobalt SS Turbo
2008 Suburban
Re: Cold start up knock?
That or its the oh so common LS Piston slap
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2014 Phatom Black 9C1 (Toy)
2000 VW Jetta TDI (Daily 420k miles)
2014 Phatom Black 9C1 (Toy)
2000 VW Jetta TDI (Daily 420k miles)