Q: As my car warms up it starts to make a knocking noise. Then stalls when I stop.

asked by on

When it starts while cold it starts fine. As it warms up it has a knocking sound and starts to shake. When I stop at a light or stop sign it will stall and went start I until it's cooled down. I replaced the spark plugs and thermostat do it doesn't over heat.

My car has 181900 miles.
My car has an automatic transmission.

Hello. Unfortunately these are typically signs of a more serious issue. Your engine may have thrown a rod. Which means the connecting rod that hold the piston in place has broken off. The only repair is to rebuild or replace the engine. You will want to have the vehicle inspected as soon as possible. There are other possible causes for the engine knocking, but they typically don’t cause a violent shaking or a stalling situation. They would include the lifters, injectors, bad or contaminated oil, and even a bad oil filter or valve. When oil is a factor, it lubricates the engine better when cold. The oil heats up and becomes thinner and has less lubricating properties. Only further testing and inspection is going to be able to tell what is causing the noise and how to take appropriate action.

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. As my car warms up it starts to make a knocking noise. Then stalls when I stop.

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: Car won't accelerate past 3000rpm

This issue could be caused by a variety of things. I would suggest by checking to be sure that the idle air control module is working properly. Also, check to be sure that the throttle body is delivering...

Q: knocking sound from the back of the car

Hello there, many faults will cause a knocking noise in your 2002 BMW 325i. The most common is the driveshaft, drive axles, differential gears, transmission mount, or the rear struts. A qualified Technicians such as one from YourMechanic will be...

Q: Crossed battery terminals now 02 Ford Explorer won't start

Hi Bryan. Thanks for contacting us today. This might be due to a damaged electrical relay or perhaps the battery cables themselves were damaged during the cross-connection. It is also possible that the ECU may have been damaged or other...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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.