My 2002 cadillac sls has a valve knocking sound when the engine is cold. on 2002 Cadillac Seville SLS

What is causing this. It has 61,000 miles and quite s down when it warms up

Asked by for the 2002 Cadillac Seville SLS
poss dirty inside of engine. rec doing an oil cleaning service to start with. that is the cheapest thing to start with. have you had regular oil changes?
1 more answer
Any noise could mean lots of things not always serious but it should be checked as soon as possible.....even minor things can become serious if put off.