Possibly a knock sensor???
 

Hi,

I have a 97 Honda Civic DX with 228K miles on it. Only during cold winter weather months my Civic knocks when I start it up. It continues to knock until it is at full operating temperature. Then it runs perfectly.

When warmed up, it does not use oil, does not have a lack of power, does not get poor gas mileage, and the check engine light is not on. It drives just as strong as it did when I bought it 200K miles ago.

Is this knocking noise because of a bad knock sensor? Can you help diagnose this problem?