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You’re on a quiet street, you press the accelerator, and the car suddenly shivers through the seat and steering wheel — but the odd vibration goes away the moment you lift off and coast. 

It’s unsettling, but it’s also a very common complaint with a manageable set of likely causes. In this guide I’ll walk you through the most probable reasons — from engine misfires to drivetrain problems and everything in between — and show you how to check, diagnose, and decide whether it’s a quick home fix or a job for a shop. 

I’ll include real, sourced facts from trusted automotive bodies and explain which symptoms point to which parts. You’ll get a clear troubleshooting path, realistic repair-cost ranges, and sensible maintenance steps to prevent the problem from returning. Read this when you want straightforward answers, not vague guesses.

Short note on sources

This guide was assembled from reputable industry and technical references to ensure accuracy and practical value. 

Key sources consulted include manufacturer technical service bulletins and diagnostic guidance, National Highway Traffic Safety Administration (NHTSA) technical bulletins on drivetrain vibration, automotive testing and repair references, and established automotive outlets and repair specialists documenting torque converter, CV joint, and engine misfire behavior. 

These sources form the basis for the diagnostic steps and the repair-cost ranges provided above. Notable references: NHTSA service bulletins, manufacturer repair guidance, and established automotive diagnostic articles.

Why the vibration only shows up under acceleration

A useful way to think about the symptom is this: coasting and acceleration put different loads on the car. Coasting mostly tests balance and suspension at steady speed; accelerating adds engine torque, changes load through the drivetrain, and shifts suspension and drive angles. 

When a part behaves fine while the car is rolling but then transmits vibration under load, that points the diagnosis toward components that only see stress when torque is applied: engine or transmission mounts, CV joints and driveshafts, torque converters, misfiring cylinders under load, or drivetrain alignment. 

In contrast, a tire or wheel balance issue usually causes vibration across a range of speeds, not only when you press the gas.

Below I’ll run through the most likely causes in order of how commonly they match the symptom, show you what to listen and feel for, explain simple tests you can do, and list realistic repair and replacement expectations.

1) Engine misfire or fuel/ignition problem under load

What it is: When an engine misfires, one or more cylinders are not producing the expected power. Under light load (idle or coasting) the imbalance can be subtle or masked; when you add throttle the missing cylinder(s) causes an abrupt torque fluctuation that you feel as shaking.

Why it fits the symptom: Acceleration increases demand on every cylinder. If one cylinder is weak (bad spark plug, failing ignition coil, dirty fuel injector, vacuum leak, compression loss), the engine stumbles only when load grows.

How to recognize it:

• The shake often comes with a rougher engine note or a choppy throttle feel.
• You may see a flashing or steady check-engine light; a flashing light usually means a misfire severe enough to risk catalytic converter damage.
• The shake is felt through the cabin and may be rhythmic — matching engine RPM pulses.

Basic checks you can do:

• Look for a stored trouble code with an OBD-II reader (P0300 series codes often point to misfires; P0301 etc. identify cylinders).
• Swap spark plugs or ignition coils (if your engine has coil-per-plug) between cylinders to see if the shake moves.
• Use a spray of carb cleaner or starter fluid around vacuum hoses while revving (only if you know how — this is a test for vacuum leaks).

What a shop will do: run a scanned live misfire count, compression and fuel-pressure tests, and injector checks. Repairs range from simple plug or coil swaps ($50–$250) to injector cleaning or replacement ($100–$400 per injector) or more complex top-end work if compression is low.

Authoritative note: industry service guidance shows misfires are classic causes of load-dependent vibration; code scanning is the first diagnostic step mechanics recommend.

2) Worn or broken engine/transmission mounts

What it is: Mounts bolt the engine and transmission to the chassis and dampen their motion. When mounts deteriorate they allow excessive movement and let torque pulses transfer to the body.

Why it fits the symptom: Under acceleration the engine twists backward and forward. If a mount is degraded or broken, that motion is no longer isolated and you feel shaking or clunking. At coasting, with less torque, the excessive movement may not occur and the vibration disappears.

How to recognize it:

• You may feel the vibration more through the seat and floor than the steering wheel.
• A loud clunk during hard acceleration or when shifting gears is common.
• Visual inspection can show split rubber or a sagging mount.

Quick checks:

• With the car parked, shift between drive and reverse lightly while watching engine movement (use caution and parking brake). Excessive movement indicates mount wear.
• A technician can pressure-test and visually inspect mounts easily.

Repair expectations: Replacing mounts is usually straightforward: parts and labor often run $150–$600 depending on vehicle and whether multiple mounts need replacement. 

OEM mounts last several years but degrade faster in harsh climates and in cars with high torque. Several aftermarket guides and service sources list this as a frequent cause of acceleration-only vibration.

3) CV joint, axle, or driveshaft issues (front-wheel- or rear-drive)

What it is: Constant-velocity joints and drive axles transfer torque from the transmission/differential to the wheels. Worn inner CV joints, a bent axle, or damaged universal joints in a driveshaft cause vibration under load.

Why it fits the symptom: A failing inner CV joint often makes itself known only when torque is applied — accelerating or under load — because the joint’s defects are stressed then. Coasting with light torque can be vibration-free.

How to recognize it:

• Feel vibration through the cabin and sometimes a rhythmic clunk or thump.
• A torn CV boot with grease loss is a telltale visual sign (but not always present).
• In some cases you might hear clicking on sharp turns (outer CV), although inner CV wear more commonly causes vibration under acceleration.

What to do:

• Inspect CV boots for tears and grease loss.
• A mechanic can lift the car and check play in the axle and CV joints.
• Replace the axle or CV joints if worn; axle replacement is common and typically done in a few hours.

Cost expectation: A replacement axle assembly (including new CV joints) typically runs $200–$800 for many cars, higher for premium models. Several repair and technical sources identify inner CV or driveshaft imbalance as standard causes for acceleration-only vibration.

4) Torque converter shudder or transmission clutch problems (automatic transmissions)

What it is: The torque converter couples engine power to the transmission. Many modern automatics use a lock-up clutch inside the torque converter to eliminate slipping at certain conditions. If the lock-up clutch or converter behaves erratically — contaminated fluid, worn clutch surfaces, or faulty control — it can shudder or vibrate when engaging, typically under acceleration or at specific speeds.

Why it fits the symptom: Torque converter shudder often shows up during light-to-moderate acceleration and can feel like a vibration or judder through the vehicle that disappears when the lock-up clutch disengages (for example when coasting or at other RPMs).

How to recognize it:

• Vibration usually occurs at particular speed or RPM bands, and sometimes only when the converter’s lock-up is commanded.
• A transmission fluid change (with proper procedure) can temporarily fix certain contamination-related shudders; persistent shudder often requires a converter or transmission repair.
• Transmission-related vibration is often felt through the whole vehicle and sometimes accompanied by rough shifting.

What to do:

• Check the transmission fluid level and condition (dark, burnt smell or metallic particles indicate trouble).
• A reputable shop will perform a transmission diagnosis; some technical service bulletins document shudder conditions tied to torque converters. NHTSA technical service bulletins and dealer service instructions frequently treat drivetrain vibrations under acceleration as transmission-related and walk techs through checks.

Cost expectation: Transmission and torque converter repairs can be expensive — fluid service and filter might be $150–$300; diagnosing and rebuilding or replacing a converter or transmission can range from $1,000 to several thousand dollars depending on vehicle and extent of damage.

5) Wheel, tire, and balance problems that only appear under torque

What it is: Imbalance, separation, or out-of-round tires, damaged rims, or unwanted runout can cause vibration. Most often these show up across many speeds, but sometimes the load and torque when accelerating change the way tires contact the road so vibration appears only during acceleration.

Why it fits the symptom: If a tire belt has partial separation or one tire has a high spot, the extra torque under acceleration can amplify the defect’s effect. Also, torque can change wheel alignment and suspension geometry slightly, revealing issues not present during coasting.

How to recognize it:

• Vibration that grows with speed and may feel in the steering if front tires are involved.
• A new vibration after recent tire work (mounting/balancing) suggests improper balancing or a damaged tire.
• Look for uneven wear, bulges, or damaged rims.

What to do:

• Have tires and wheels professionally balanced and inspected (road force balancing if available).
• Replace tires with suspected separation or severe wear.
• Check wheel bearings and hubs for play; worn bearings can also transmit vibration under load.

Authoritative note: tire-related vibration is a leading cause of NVH complaints and AAA research points to tire characteristics and wear affecting vibration and noise; shop balance and road-force testing are common remedies.

6) Brake-related dragging or warped rotors

What it is: If a caliper is sticking or a caliper slide is seized, brakes can drag under some conditions and cause vibration under acceleration as the pads contact the rotors. Warped rotors usually cause vibration during braking, but certain defects can create a feel during acceleration too.

Why it fits the symptom: Dragging brakes add uneven resistance and heat; when torque is applied the uneven load can translate into shaking. This is less common than other causes but worth checking.

How to recognize it:

• You may smell burning or notice reduced fuel economy.
• Heat on one wheel after a drive indicates a sticking caliper.
• A visual check of rotor condition and caliper movement on a lift will reveal issues.

What to do: Service calipers, replace pads or rotors as necessary. Typical cost ranges from $150–$500 per axle depending on parts and labor.

7) Bent axle, failed driveshaft, or universal joints (rear-wheel and four-wheel drive)

What it is: On rear-wheel-drive or body-on-frame vehicles a bent driveshaft, worn U-joints, or damaged prop shaft can cause vibration that appears only when torque is applied.

Why it fits the symptom: These components carry torque along the vehicle’s length. Under acceleration the shaft dynamics change and defects become apparent. Coasting at constant speed may not excite the same harmonics.

How to recognize it:

• Vibration often intensifies with acceleration and may be accompanied by a growling noise.
• Visual/mount inspections can show looseness or missing balancing weights on a driveshaft.
• Mechanics check U-joint play and vibration at various RPM ranges to isolate the issue.

Typical fix: U-joint replacement or driveshaft repair; costs vary widely — a U-joint job might be $100–$400; driveshaft replacement or balancing more.

A practical step-by-step troubleshooting plan

1. Note exactly when it happens. Is it from a stop, only between certain speeds, or anytime you add throttle? Document RPM and speed ranges.
2. Scan for engine trouble codes with an OBD-II reader — misfires or transmission codes are prime clues.
3. Rule out tires/wheels: check pressure, visually inspect for bulges or damage, and balance test at a shop.
4. Check engine and transmission mounts visually and by feeling engine movement during a gentle rev in park/neutral.
5. Look at CV boots and axles for tears and grease loss; listen for clicking on turns (outer CV) and vibration under straight acceleration (inner CV).
6. Check transmission fluid for level and smell; replace or have a shop pressure-test the transmission if it smells burnt or is contaminated.
7. If none of these show, have the driveshaft, U-joints, and torque converter checked by a qualified technician; they have the gear and lift to reproduce and measure vibration.

Typical repair-cost ranges (quick reference)

• Spark plug or ignition coil: $50–$300.
• Fuel injector cleaning or replacement: $100–$500 per injector.
• Engine or transmission mount replacement: $150–$600.
• CV axle replacement: $200–$800.
• Brake caliper service or rotor replacement (per axle): $150–$500.
• Transmission fluid service: $150–$300.
• Torque converter or transmission rebuild/replacement: $1,000–$5,000+ depending on vehicle.

Prices vary by make, model, region, and labor rates — always get written estimates from reputable shops.

Preventive care that reduces the chance of acceleration-only vibration

• Keep up with scheduled ignition and fuel system maintenance: fresh plugs, coil checks, and clean fuel delivery.
• Inspect tires at every oil change and replace tires showing belt separation or uneven wear.
• Service transmission fluid and perform recommended inspections — many torque converter issues stem from contaminated or neglected fluid.
• Replace engine mounts proactively if you notice increased noise or vibration during normal operation.
• Fix torn CV boots quickly — loss of grease accelerates CV joint failure.

AAA and vehicle maker service guides repeatedly emphasize preventive maintenance as the most cost-effective way to avoid complex NVH problems later.

When to get professional help immediately

• The vibration is getting worse quickly or accompanied by smoke, burning smell, or fluid leaks.
• You hear loud clunks or grinding, or the car pulls strongly to one side.
• The vehicle’s check-engine or transmission warning light is flashing.
• You lack tools or confidence for safe inspections.

A qualified shop can reproduce the symptom under controlled conditions, use diagnostic tools, and provide a written estimate.

Final checklist — what you should do right now

1. Record the symptom details (speed, RPM, load).
2. Scan for engine/transmission codes with an OBD-II reader.
3. Visually inspect tires, CV boots, and mounts.
4. Have a shop balance the wheels and check runout if tires look fine.
5. If still unresolved, book a drivetrain/ transmission diagnosis — give the shop your notes so they can reproduce the symptom quickly.