Why Does My Car Shakes at Idle but Smooths Out While Driving?

If your car shudders when it idles and then smooths out when you accelerate, the problem may be related to your engine mounts. These are designed to help absorb vibrations and keep your engine from shaking too much.

If they’re worn out or damaged in any way, they won’t do their job properly. This can cause your engine to shake at idle speeds, but not while driving. There are a few ways to check if this is the problem first, take a look at your oil level if it’s low or dirty, you might want to drain and refill it.

Next up is a visual inspection if something looks broken or cracked on one of the mounts, it’ll need replacing immediately before further damage occurs. Check under the hood for any loose bolts or screws that could be causing the problem a quick tightening will often solve this issue.

What causes a car to shake and vibrate?

The most common cause of this issue is a bad wheel alignment, which can be caused by anything from hitting a pothole to simply driving too fast for too long. The reason this causes your car to shake and vibrate is that it changes the angle at which your tires meet the road.

If you’re experiencing this issue, take your car in for an inspection right away. It’s easy enough to correct the problem with new tires and an alignment, but if left unchecked it can lead to more serious problems down the line.

What are the symptoms of a bad engine mount?

The engine mount is designed to hold your engine in place. It helps absorb the vibration from the engine and allows the engine to run smoothly.

Engine mounts can wear out over time, which causes them to become loose or cracked. This leads to an increase in engine vibration and noise, which may cause your car to shake at idle but smooths out while driving.

How much does it cost to replace the engine mounts on my car?

This really depends on what kind of replacement parts you need—and how old your car is. If you’re looking at new engine mounts for an older model and it hasn’t been maintained very well throughout its life, expect to pay somewhere around $400-900 for new ones.

But if you’re looking at new motor mount replacements for a newer model and it’s been maintained well throughout its life, expect to pay somewhere around $150-400 for new ones.

What can I do to fix it?

Check your tires. Make sure they’re in good shape and have plenty of treads left. Check the alignment of your car. If it is out of alignment, this could be causing the shaking at idle. If those don’t work, try checking the balance on your tires or replacing them if needed.

Worn Out or Faulty Air Flow Meter

If your car is shaking at idle but smoothing out when you’re driving, it could be because the airflow meter is faulty. The airflow meter measures how much air is coming into your engine, and if there’s anything wrong with it like a bad sensor it will show up in the form of shaking at idle.

If this happens, you’ll need to have your car checked by a mechanic to make sure nothing else is wrong.

Why does it shake?

The first thing to try is adjusting the idle speed. The idle speed is the speed that you want your engine to run when you’re not pressing on the gas pedal. If your engine is running too fast, it can cause shaking in the car when it’s idle.

To fix this problem, watch for a dial on your dashboard labeled “idle speed.” Turn that dial until the number matches what is recommended by your car’s manual.

Another possible cause is related to the clutch. If this part is worn down or old, it can make the car shake when it’s idle because it can’t keep up with how fast the engine needs to run in order to keep itself running smoothly.

To check if this is causing your problem, check under your hood and look for an area called a clutch. If this looks worn down or damaged, consider replacing it as soon as possible.


The car’s engine is not adjusted correctly, and it needs to be fixed. The engine shakes at idle because there is too much air being sucked in, and the car smooths out while driving because there is less air being sucked in.

Steven Hatman
Steven Hatman

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