Q: Knocking sound when idling or stopped 1993 Chevrolet Lumina APV

asked by on

There is a rhythmic knocking sound coming from the left side of the engine (facing the engine from the front) near the serpentine belt. On the road you can't really hear it, it gets really loud when idling at a light. Then in park and running it's still there just not as loud.

My car has 230000 miles.
My car has an automatic transmission.

Hello - the rhythmic knocking you hear could be something driven by the serpentine belt (i.e. AC compressor) or the belt itself. It is also possible that this an internal noise - like the timing chain, which is immediately behind the serpentine belt on the engine. Removing the serpentine belt, then starting the engine for 20-30 seconds won’t harm the engine, but would narrow the problem to inside the engine or something belt-driven. I would recommend getting this checked out soon, as additional damage may be occurring while you drive further. A mobile, professional mechanic, such as one from YourMechanic, will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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. Knocking sound when idling or stopped 1993 Chevrolet Lumina APV

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: We had a flood in Houston I have a 95 chevy blazer checked all the fluids everything is fine no water in them I let it sit went to

Hi Brian. First off, our thoughts are with you and everyone else in the Houston area. In regards to the issue with your Blazer, the flood and excessive water plays havoc on ignition and electrical systems. It's likely that one...

Q: My alternator reading that the solenoid is bad when I took it off and took it to the shop they did a test on the alternator in the

Hi. There could be several things going on here. The battery for the car could be going bad or already is bad, causing the alternator to read low voltage. The battery needs to be tested as well. The fuse for...

Q: My car knocks - 2006 Toyota Yaris

Hello. In newer vehicles with electronic fuel injection and ignition systems, engine knocking due to bad fuel or spark is extremely rare. In most cases, if the knocking sound is consistent and increases in speed as the RPM increases, it's...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...