Why Does My Car Shake When I Accelerate? 5 Common Causes

Why Does My Car Shake When I Accelerate? 5 Common Causes

INTRO

A car that shakes when you press the gas but smooths out when you coast is telling you something specific — power isn’t transferring cleanly somewhere between the engine and the wheels. It might be a worn joint, a misfiring cylinder, or a bad mount. Here’s how to tell which one based on what the shaking feels like and when it happens.

SUMMARY

CV joints are the most common cause in front-wheel drive cars — clicking when turning is the giveaway
Engine misfires cause shaking that’s also present at idle — acceleration just makes it worse
A clunk when shifting into gear or a shudder the moment you hit the gas points to motor mounts

QUICK ANSWER

If the shaking only happens during acceleration and goes away when you coast, start with the CV axle. If it’s also rough at idle, suspect a misfire — check for a check engine light and have codes read. If you hear a clunk when putting the car in gear, motor mounts are likely. A clicking sound during sharp turns almost always means a CV joint.

Why Acceleration Triggers Shaking

Acceleration puts load on every part of the drivetrain — the engine, transmission, axles, joints, and mounts all work harder the moment you press the gas. Any worn or failing component that might feel fine at idle gets exposed under that load. The location of the shaking and when it happens narrows it down quickly.

HOW TO NARROW IT DOWN — 5 Causes

1. Worn CV Axle or CV Joint

The CV (constant velocity) axle transfers power from the transmission to the wheels. CV joints at either end of the axle allow the wheel to move up and down while still receiving power. When they wear out, they develop play — under acceleration that play causes wobbling instead of smooth rotation.

Signs: Shaking during acceleration that clears up when coasting. Clicking or popping sound during slow sharp turns — this is the clearest sign of a failing CV joint.

This is the most common cause of acceleration shaking in front-wheel drive vehicles.

Fix: CV axle replacement — typically $200–$600 depending on the vehicle. Don’t delay — a failed CV joint can leave you stranded or cause the axle to separate while driving.

2. Engine Misfire

A misfiring cylinder causes the engine to produce uneven power. At idle it’s a rough shake; under acceleration the demand for power makes it much more noticeable.

Signs: Shaking also present at idle, sputtering or hesitation when pressing the gas, check engine light on. A flashing check engine light means severe active misfires — don’t continue driving.

Fix: Read the fault codes — they’ll identify the problem cylinder. Usually spark plugs or a failing ignition coil. See the engine knock and rough idle articles for more detail.

3. Bent Wheel or Damaged Tire

A bent rim or a tire with a broken internal belt creates an out-of-round rotation. The faster the wheel spins, the worse the vibration — and the force of acceleration amplifies it.

Signs: Vibration tied to speed as much as throttle input, may have started after hitting a pothole or curb.

Fix: Check tire pressure first — uneven pressure makes vibration worse. Then have wheels inspected for bends and tires inspected for internal damage. A bent wheel needs replacement; a damaged tire needs replacement.

4. Bad Engine or Transmission Mounts

Mounts are rubber-and-metal brackets that hold the engine and transmission to the frame. When you press the gas, the engine tries to twist — good mounts absorb that movement. Failed mounts let the engine shift too far and slam against its stops.

Signs: Clunk or thud when shifting into gear or hitting the gas, shaking that feels like it’s coming from under the hood rather than the wheels, engine visibly shifting when you rev it.

Fix: Mount replacement — $200–$600. Usually a mechanic job due to the weight of the components involved.

5. Driveshaft or U-Joint Issues

In rear-wheel drive, truck, and AWD vehicles, a driveshaft sends power from the transmission to the rear axle. U-joints at either end allow the shaft to flex with suspension movement. A worn U-joint or slightly bent driveshaft vibrates increasingly as speed rises.

Signs: Vibration that gets progressively worse with speed, may feel like a whole-body shudder more than a steering wheel shake. Common in trucks and SUVs.

Fix: U-joint replacement is relatively inexpensive — the part is cheap but access varies by vehicle. A bent driveshaft needs balancing or replacement.

TIPS

Only shakes when accelerating, smooth when coasting → CV axle or motor mounts first.
Clicking when turning → CV joint, almost without exception.
Also rough at idle → engine misfire, not a drivetrain issue.
Clunk when shifting into gear → motor mounts.
Whole-body vibration that gets worse with speed in a truck or SUV → driveshaft or U-joint.
Read fault codes before replacing anything — a free scan at any auto parts store eliminates guesswork on misfire-related shaking.

TROUBLESHOOTING

Shaking only during hard acceleration, fine at light throttle CV joint or motor mount — both are more affected under heavy load. Try accelerating gently and gradually increasing throttle to feel where the threshold is.

Clicking when turning plus shaking when accelerating CV joint failure — these two symptoms together are a near-certain diagnosis. Replace the CV axle before the joint fails completely.

Shaking started after hitting a pothole Bent wheel or damaged tire is the first thing to check. Have the wheel inspected before assuming it’s mechanical.

Whole car shudders when shifting from Park to Drive Motor mount — the engine is moving too much when torque is applied. Try revving slightly in park and watching the engine; excessive movement confirms it.

Shaking gets worse at highway speeds in a truck Driveshaft or U-joint. At highway speeds a worn U-joint creates a strong vibration that can be felt throughout the cabin.

FAQs

Why does my car shake when I accelerate but not when I coast? Because acceleration puts load on the drivetrain — CV joints, motor mounts, and the driveshaft all work harder under power. A worn component that feels fine at rest gets exposed the moment you press the gas.

Can bad spark plugs cause shaking when accelerating? Yes — a misfiring cylinder that’s manageable at idle becomes much more noticeable when the engine is under load. Usually comes with a rough idle and a check engine light.

Is it safe to drive with a bad CV joint? Not for long. A worn CV joint that’s clicking can fail completely, which can cause the axle to separate while driving. Get it replaced promptly.

What does a bad motor mount feel like? A clunk or thud when you shift into gear or hit the gas, plus a shaking sensation that feels like it’s coming from under the hood. The engine may also visibly rock if you open the hood and rev it.

How do I know if it’s the CV joint or the driveshaft? CV joints are more common in front-wheel drive cars and produce a clicking sound during sharp turns. Driveshaft issues are more common in rear-wheel drive trucks and SUVs and produce a whole-body vibration that increases with speed.

Next Step:

If your car is shaking but it actually feels worse when you’re just sitting still at a light, check this out: 👉 Car Shakes at Idle But Smooth When Driving (Causes + Fixes)

Car Shakes at Idle But Smooth When Driving (Causes + Fixes)

About The Author

Dmitri is an automotive professional with experience in vehicle operations, financing, and ownership education. He writes practical, easy-to-follow guides to help drivers make informed decisions about car maintenance and comfort features.