would air in the water pump line make a sound like someone knocking on a door? on 1998 BMW 328i

please excuse my inability to use car technicial terms, I'm just a college student with very little knowledge of how my car works.
I am very thankful for anyones help since I live on a college students budget.

Asked by for the 1998 BMW 328i
Most likely Not, No. The noise im betting your hearing is your fan running into something.
thanks so much for the response and suggestion. I will have someone check it out for me!
2 more answers , 2 more comments
Nope, not going to be in the cooling system. Check all your fluids and pay special attention to the plastic fan. Make sure it is not rubbing or missing blades. We are the large BMW shop in Vallejo. I already replied to the fog light question. Call Adrian at Milt's Service Garage for more info (707)643-7548
Once again I appreciate you responding to my questions with patience and good suggestions!
What you are discribing is anything from a rod or crank bearing problem to a broken exhaust mount. Take it in and have it checked.
I truly appreciate your response and advice. I will take your advice and have someone check the issues you suggest it might be!
Qualified Local BMW Shops
Qualified BMW Shops For This Repair
6351 Dublin Blvd
Technical Ability
Tools & Equipment
Customer Service
Customer Amenities
(925) 203-9158