How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask john c Your Own Question
john c
john c, ASE Certified Technician
Category: Pontiac
Satisfied Customers: 238
Experience:  ase master, asep grad,853 gm certs, gm master cert, 18 years gm tech
Type Your Pontiac Question Here...
john c is online now
A new question is answered every 9 seconds

Why is my car making a knocking noise when accelerating?

Resolved Question:

My car is making a knocking noise when I accelerate and sometimes when it is park. What could it be? How much does it cost to get it repaired?

Submitted: 8 years ago.
Category: Pontiac
Expert:  john c replied 8 years ago.

It depends on the knock. A lighter sounding tap type knock is usually the upper end and would be the lifters. A deeper sounding knock would be the lower end like the rod or main bearings.
Either way it is not a very cheap repair. So its best to know exactly which one you are looking at. If its the lifters its worth repairing. If its the rod or main bearings, it would be a lot cheaper to replace the engine.
The best thing to do is to go have it looked. At the most you will pay is an hour check out and know exactly what your looking at.
Hope this helps. Let me know if I can further assist you.

Customer: replied 8 years ago.

The car is running fine. So do you think I should keep driving it?

Expert:  john c replied 8 years ago.

Either knock will not effect the way the car runs.
If its a lifter noise you will be fine for a good while. If its a rod or main bearing your time is very limited and it will leave you stranded.
The best thing to do would be find out which one it is. Then you will know if you have time or not. Hope this helps. Let me know if I can further assist you.

john c and 4 other Pontiac Specialists are ready to help you