Thinking about purchasing a new car? Use our new Car Loan Calculator to estimate your monthly car payment!

How to Fix a Knocking Rod

by Sharin Griffin

A knocking engine rod is a sign of distress from the inner workings of your vehicle. There are several reasons why an engine rod would begin to knock. Some are easy fixes others require extensive work. This does not mean your engine is beyond repair. Before calling the mechanic there are some steps you can take to stop engine knocking and stabilize your engine rod before complete replacement is necessary.

Driving your vehicle onto a set of mechanic's ramps. Place an oil pan underneath your oil pan. Remove your oil cap located underneath or next to your oil pan. Drain the oil from your vehicle completely. Replace the oil cap. Remove the oil filter by fitting an oil-filter wrench around the middle of filter and turn clockwise. Place a new filter in the slot, fit the wrench around it and turn counterclockwise to tighten. Replace the drained oil with four to five quarts of fresh oil.

Remove the oil pan and check your rod bearings. When your rod bearings are loose you will hear a knocking in your engine. Tighten or replace the bearings as needed. If your bolts holding the rod bearings are the wrong size, replace them.

Pour fuel-injection cleaner into your vehicle's gas tank when you fill up. Grime from the bottom of your gas tank makes its way into the engine, causing rod knocking. Cleaning your fuel-injection system will help clear out the grime and stop the knocking. If your car has a carburetor, do not use fuel-injection cleaner. Purchase carburetor cleaner and spray it directly onto your carburetor.


  • If your rod bearings are damaged beyond repair, you may require an engine rebuild. Contact your local mechanic to have your engine rebuilt.

Items you will need

About the Author

Sharin Griffin has been a freelance writer since 2009, specializing in health-related articles. She has worked in the health-care industry as a certified nursing assistant and medical technician. Griffin's medical expertise encompasses bariatrics and geriatric care, with an emphasis on general medicine. She is completing an associate degree in health-care administration from Axia University.

More Articles

Photo Credits

  • Thinkstock/Comstock/Getty Images