Q: Engine knock at startup

asked by on

My car 2004 Chevrolet Classic with 193,000 miles on it started knocking. I parked it. The radiator reservoir was empty so I filled it. Cranked the car and the sound began to quiet bit did nit go away. Now when the car is started it knocks hard for a second at startup then dulls to barely noticeable. It knocks more noticeable in reverse. Oil was changed after the knock began as well. What could cause this?

My car has 193000 miles.
My car has an automatic transmission.

Hello there. In most cases, an engine knocking sound at start up is caused by hardware inside the cylinder head of the motor that is loose or is not properly lubricated. As the engine starts, and oil is circulated to the top of the motor, the knocking will subside. This type of noise can also be caused by a loose belt or pulley. As such, it is probably best to have a professional mechanic come to your location and complete a car is making a noise inspection, so they can determine what is causing this noise.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Engine knock at startup

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Truck is sluggish going uphill

Hello. There could be a problem with your transmission's lower gears. The transmission uses the lower gears when the truck has to pick up speed, go up hills, and haul heavy loads. If the low gears are not operating properly...

Q: Car starts but immediately quits

If you have replaced all of those components and you're still getting issues then the problem should be in the fuse box with the body control module fuse located in it (on the driver side) or there is an open...

Q: My vehicle was hotwired and vandalized

There will be a few things that will need to be addressed. A qualified mechanic, like one from YourMechanic, will need to drain all the gas/sugar from the gas tank and all lines. And the ignition switch and wiring will...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.