The car shaking on cold start happens if you park your vehicle outside in the cold weather all night.
In the morning, when you are ready to go to work, the car suddenly vibrates strongly after starting. This situation is not uncommon.
This article will provide a list of enemies causing this frustrating issue.
Fortunately, this problem is not a big deal, and you can resolve it. Keep reading until the end to learn the best methods to protect your car from a cold start.
Without further ado, let’s get started!
What Trigger Car Shaking On Cold Start?

In general, the vibration happens mainly due to the reduced coolant temperature needed to run the engine in the open loop mode.
And the whole procedure to regain the heat requires excessive working, generating unwanted engine shake.
Also, there are a bunch of causes for the engine shake. Here are several reasons you can refer to figure out what factor triggers the engine shake:
Low Fuel In The Canister
The first reason seems very trite, but you usually skip checking. Car shakes on cold start may arise due to depletion in the fuel canister.
A lack of fuel burnt is insufficient to start the engine, even harder in cold weather. So do not forget to have a tank filled with the required petrol.
If the canister is still full, and the shaking keeps occurring, it means the problem has worsened. Scroll down for deeper causes.
Use Bad Fuel
You may not believe it, but low-quality fuel is another culprit leading to the issue of the car shaking in cold weather.
The petrol pumps nowadays usually cheat on the quality of fuel. And you have no way to detect the low-quality fuel before refilling the tank.
Nevertheless, you can self-check after driving home. Take a small basin and pour into around 2 liters of fuel, then wait for a couple of hours. If the fuel is free of water, there is nothing to change.
Otherwise, you will see the water sink to the bottom, and the fuel will float on the surface. It would be best if you acted fast by changing to a more qualified gas station.
Also, not to mention the diesel engine. The cold temperature will freeze the diesel terribly. So the start cold will make the engine stall instantly. Or else, the diesel car shakes when starting.
A Discharged Car Battery
Sometimes, your car shakes on cold start because of a discharged car battery. Most drivers usually charge many electronic devices, even when the engine is off.
This equipment will consume a remarkable energy ratio, disturbing other engine components. Take the ignition coil and fuel pump for examples; the entire battery discharging will mess up the normal operation of these parts.
Furthermore, the internal combustion engine is also an impacted part most of the time. So do not skip rechecking this core element.
A Bad Fuel Pump
Low-quality fuel pumps would be a worthwhile reason why the car vibrates when cold. In other words, the fuel filter clogging may lead to an error in engine operation.
More specifically, the fuel pump will clog up an optimal fuel rate through itself to cylinders. Or else, the process will take place slowly, which enhances the stall duration.
An insufficient optimal fuel quantity will aggravate the engine operation, causing light engine shake.
However, the situation may worsen if the fuel filter is too old to pump energy. Then, you can feel unexpected strong vibrations on a cold start.
The point is to maintain the filter periodically and replace a new fuel pump if necessary.
Bad Spark Plugs
A failed spark plug can also explain why the car shakes when starting up cold. It blocks the proper ignition of the fuel to air mixture in the cylinders, causing the awful uneven misfire.
That issue makes the engine run harshly, thereby leading to engine vibration and humming noise when increasing the speed.
All you need to do is to unlock the ignition system and discover the malfunctioning place. The worn-out spark plugs require a whole new replacement.
Should they be dirty, find a proper tool to clean them well and return them to work as usual.
Besides, use a multimeter when the issue lies in the ignition cables. Check the ignition coils to see whether there exists any resistance.
It would be best if you regularly had your vehicle checked. This habit helps you to minimize the engine vibration greatly.
Faulty Spark Plug Wires
The spark plug wires sometimes get loose, so you easily notice the car shakes when starting cold.
These wires include fuel-to-air mixture, radiator hose, or vacuum hoses; all are important elements in the engine compartment.
If that problem arises, the engine will work abnormally and trigger a strong engine shake due to insufficient requirements.
Faulty hoses are the simplest to mend. Just replace an old damaged wire system with a new one.
Worn-Out Timing Belt Or Timing Chain
When there is a worn-out timing belt or chain, you can feel that the car shakes when cold. The intense freezing weather might deteriorate the belt and chain.
However, those elements do not have a proper alternative. Thus, make sure to check it regularly.
Problems With ECU
When the engine shakes until warmed up, the problems with the ECU or electronic control unit system may be to blame.
We bet you will have no idea how to DIY; let’s turn to experts for a professional inspection and proper fixing ways.
Go to a good auto shop to get the ECU system checked quickly. Otherwise, you can not imagine how terrible the influences may turn out.
Bad Engine Mounts
Another common reason must come from the motor mount issue.
The bad compression in cylinders will destroy the internal combustion engine, making it dreadfully damaged. So the car normally starts first but then slowly turns idling.
Moreover, the engine temperature has not increased, making the vehicle vibrate intensely.
After a few minutes, the heat from burning oil will warm up the system. And the structure rubber will soften and lower the vibration level.
So, quick action is necessary when your vehicle encounters bad engine mounts.
Dreadful Fuel Injector
Fuel injectors spray a desired fuel quantity into the internal combustion engine.
If there is dirt buildup, the spray can work effectively. As a result, a misfire will fire the cylinder unevenly, thereby leading to strong vibration.
You can swap out injectors with cylinders to detect the poor injector. In addition, regularly changing a new fuel filter is the best offer to minimize that issue.
Faulty Idle Speed Sensor
This symptom happens rather commonly with most vehicles. The faulty idle speed sensor makes the RPM float on a cold engine.
When the speed suddenly spikes, the crankshaft speed will plunge significantly. The engine will turn into the stall state, and the engine shake will appear.
Other Reasons
Apart from all the mentioned points, we never skip a rare but still happening symptom – exhaust system leak.
In every ignition in the combustion engine, the sound is like an explosion.
And the mufflers from the exhaust system will quiet down that excessive noise during operation. So if the mufflers get leaky holes, they can not work well to reduce the explosion.
So the air leak triggers an annoying noise resonating with the engine that will cause an awful shake. The best fix is to take a periodical check on mufflers and pipes from the exhaust system.
If there are any cracked or broken holes, do not hesitate to replace a new one for better operation, especially on cold starts.
Does Cold Start Harm The Car Engine?
Not really. Cold starts do not harm your vehicle, given that you operate properly. On the contrary, that process allows your car to recover the desired temperature.
To be specific, oil cooling out too long will initiate the cold starts, and the oil will be heated.
Thus, the oil settled at the deep base will pump up and lubricate other moving parts. As a result, the procedure will regain the desired heat for the engine to restart.
What is more? The engine temperature increases depending on how the oil’s viscosity modifies over a couple of overnights in the parking lot.
The lubricant becomes thicker in an extremely frigid region, making it hard to deliver oil. Hence, the whole operating system will have limited functions. By then, cold starts will ease the problem.
The lubricating oil gradually gets warm, thereby becoming thinner and melting. This process results in smoothing the flow and function of the operating system.
How To Protect The Engine From Damage During A Cold Start
Starting your automotive properly during cold weather can minimize serious damage. Also, the way you proceed operating after driving off will defend your engine system against harm.
Here are some effective suggestions we would like to offer:
- Let the engine idle for a while after kicking off. This way, the oil has enough time to circulate and lubricate the whole system.
- Do not incessantly rev the engine left under cold temperatures, which harms your car. If the nonstop racing happens, you can not imagine how it will aggravate the friction, which is inherently the primary obstacle in a cold start.
- Keep the choke valve closed on cold starts, especially if your vehicle has an old carbureted engine. This tip will prevent your car from constantly stalling.
- After driving off, do not rush at a sudden high speed. It’s better to drive slowly for several minutes. This way gives the engine more time to reach the required engine temperature.
In Conclusion
To summarize, we have provided a list of possible culprits behind the issue of a car shaking on cold start. Moreover, you must know the right methods to safeguard the engine when the cold starts.
Have a mechanic check if you are a new driver and do not know what to do.
Bring the car to a reliable auto repair shop for professional tests and proper fixes.