Why my car makes metal knocking sound every time I accele...

Q: Why my car makes metal knocking sound every time I accelerate, and it gone when I release acceleration pedal? It happens at 25+mph

asked by on July 20, 2017

Why my car makes metal knocking sound every time I accelerate the speed, and it gone when I release acceleration pedal? It happens at speed of 25 mph and up. Recently, the noise is louder. The noise keep coming as long as I keep foot on and maintaining the same speed at 25 mph or higher. I can feel the knocking force by my left foot. Specifically, I feel the noise comes underneath of my car from the driver side. That noise is louder when I go straight than when I steer the wheel. I'm not sure what is that sound, and where is it from. Please help me identifying that sound.

My car has 229000 miles.
My car has an automatic transmission.

What you are describing sounds like a failing CV joint. A CV (Constant Velocity) joint is a shaft that connects the transmission to the wheels, essentially transferring the power from the drive train directly to the wheels. The CV joint is packed with a special grease and sealed tight with the rubber or plastic boot, that is held in place with two clamps. The most common problem with the CV joints is when the protective boot cracks or gets damaged. Once this happens, the grease comes out and moisture and dirt get in, causing the CV joint to wear faster and eventually fail due to lack of lubrication and corrosion. When the CV joint becomes damaged or worn, you may hear a clicking, clunking or popping sound coming from this area as the weight of the vehicle puts pressure on this area and shifts back and forth and side to side. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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

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

HI I was driving home today and noticed while I was at a traffic light my oil light started to flicker.

Engine oil pressure may be below the requirement at idle. To determine that, temporarily install an external pressure gauge and verify that you have at least 5 PSI at idle, although you should compare against the pressure specification set forth...

Toyota Yaris 1.0 VVTi GS problem starting at normal temprature

The most likely common problem with these symptoms is a sticky/dirty idle air control valve, which either needs to be cleaned or replaced. Other possibilities is a clogged fuel filter, failing fuel pump relay, or fuel pump itself. I would...

Truck won't start, but lights come on and flicker

What you are describing sounds like a faulty starter solenoid. A faulty starter solenoid will generally produce a clicking sound when turning the key. The starter solenoid is located on the starter and has internal electrical contacts that transmit electricity...

Related articles

The Best Used Cars to Buy for Long Commutes
Most Most of us are faced with the prospect of commuting back and forth to work on a daily basis, but some have a much longer drive than others. When it comes time to buy a car, you need to...
Top 10 PZEV Cars for Eco-Friendly Drivers
Teddy Leung / Shutterstock.com The whole idea of a PZEV (that is, a partial zero-emissions vehicle), seems paradoxical. You’d think it’d have to either be zero-emissions or not in the category at all. But as contradictory as...
A Buyer’s Guide to the 2012 Subaru Impreza
The The 2012 Subaru Impreza is sure to be a crowd pleaser. The already wildly popular compact sedan got a new redesign for 2012, giving it sleeker lines and a more contoured look, but that’s not all there is to...