cold start up knock?

[eric69cam]

i have a 2000 silverado with a 5.3. it has what sounds like a knock for the first 20seconds or so on start up.:brick: i've heard from a few people i know with as little as 30,000 miles that theirs does the same. does anyone know the problem? any help would be appreciated

[RandyW]

My Tahoe developed it at about 80000 miles. It was just carbon build up, though I don't baby it. I towed a car through the mountains and mine went away, I guess the extra heat and rpm broke the carbon loose and cleaned it out!:yup:

[eric69cam]

well i can't really say i baby mine at all. i tend to have a heavy foot. it just seems to be pretty stubborn. i am in the process of changing plugs and wires. wires are done through msd. just waiting on the plugs. i guess i'll see what that does for me. thank you though

[RandyW]

I never babied mine either, but it still had a major carbon build up, the best way to get rid of it is to 4 wheel in deep sand or tow a heavy load at high speed up hill.

[chevyguy789]

you may want to check out another forum. i often check out pickuptruck.com

do a search on cold start knock. you'll find many remedies of what other people have tried.

[Tyler_LS1]

my is the same way on a cold start check sig for info..