After you sit with the car running, the car starts smoking and eventually starts shaking

I start the car, car runs fine after awhile and after I park the car and sit with the car still running, it seems as if the engine starts shaking and after awhile starts smoking! Is it overheating? What could be the problem?

My car has 110000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi, thanks for writing in. It all depends where the smoke is coming from. If it is from the exhaust then your engine be running rich and starting to foul out the spark plugs. Have the computer tested to see if any codes are present that could indicate what is causing the smoke. If you see smoke from the engine compartment then you may be running the engine hot due to low airflow over the radiator. Have the cooling fan checked to make sure it is running. If it is running and the vehicle has the AC running and the blower is on or near high then you may be using more energy than the alternator can keep up with. This can cause the radiator fan to not turn as fast as it should and let the temperature to rise if idled for long periods. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Smoke often leaves car engines as a result of overheating. This can be caused by faulty wire casings, heated residues on the engine block and overheated liquids including oil, transmission fluid and brake fluid. There may also be a fault in your coolant system, or your engine may not have enough lubricant.
White smoke from the exhaust: This could be steam caused by condensation in the exhaust pipe or a more serious issue caused by an engine coolant leak. Excessive amounts of white smoke could indicate head gasket failure.
Wispy White “Smoke” When You Start Your Car

Starting your car will warm that condensation, turning it into steam. As the exhaust system warms up, the condensation will disappear, and the white steam along with it.

Oil Spillage and Leakage – If oil spills on the engine, it can burn and send up smoke without there being any overheating. The smoke will be blue or gray. Leaking Coolant – If you see white smoke under the hood, it`s most likely burning coolant that has come into contact with the hot components beneath your hood.
It`s normal to see a small puff of white smoke coming from your tailpipe when starting your car after it sits overnight — it`s only water vapor. You may also see steam rising from under the hood on a rainy day as water burns off the radiator or exhaust.
Faulty fuel injector: Another possible cause of excessive white smoke from the exhaust pipe is a bad fuel injector. The injector can leak or become stuck open and deliver too much liquid fuel into the combustion chamber. The excess fuel causes thick white smoke to be produced and released from the exhaust pipe.
Black exhaust smoke

When your exhaust pipe gives off black smoke, one of the things to get worried about are bad or worn out spark plugs. It means fuel burning in the combustion chamber is not being done 100 percent or burnt fully. It also means that air is not being well mixed with fuel to burn effectively.

Sign #2: You Can See (And Smell) Engine Exhaust

So if you see anything that looks like smoke, it could be a sign that the oil is old (if it`s not a sign of a major mechanical fault like a cracked head gasket). Ditto for if you can smell any hint of burning oil in your exhaust.

One possible reason for white smoke coming from your car`s exhaust is that the engine is burning oil. This can happen if the oil level in the engine is low or if the oil seal is leaking.
Low coolant can sometimes cause a head gasket on your engine block to blow. If this happens, you may notice smoke emitting from the engine or tailpipe, a loss of power, engine knocking sounds, or decreased efficiency.
The radiator prevents overheating by cooling the fluid that flows around the engine block to dissipates the engine`s heat. When you see smoke coming from the radiator, it is an indicator that the radiator has not been able to do this job and the car is overheating as a result.
That said, a severely overheating engine can cause the cylinder walls or the pistons themselves to warp, bend and deform. This will cause the perfect seal between the piston and the rest of the engine to lose integrity. Oil could be forced past the piston rings and into the engine, where it will burn the oil.
Technically speaking yes you can use plain water in your cooling system but it isn`t recommended as a long term solution and certainly not in extreme weather conditions.
Oil Leaks. Using synthetic oil in the wrong engine can cause gaskets and seals to leak. Oil leaks accumulating under the car and white smoke coming from the exhaust could be signs that you`ve used the wrong oil.
White Smoke Coming From Exhaust: Explained

White smoke from your exhaust means coolant is exposed to your engine`s combustion process. In most cases, this is the result of a blown head gasket, but a cracked engine block or cylinder head could also be the cause.

White Smoke

In extreme cases, you will need to replace your head gasket. At the first sign of white smoke you can try head gasket repair treatment to seal the leak before you do serious damage to your engine.

White Exhaust Smoke

White smoke billowing out of your exhaust means that coolant is likely leaking into the cylinders. This usually happens when there has been a breach in the head gasket, which makes the coolant create this white steam.

If your vehicle`s engine overheats, it could be due to failing spark plugs. Overheating can happen for a number of reasons that can cause your engine to be too hot. This can harm your engine parts and lead to expensive repairs down the line.
White smoke most likely would indicate that water or coolant is getting into the combustion chamber or exhaust port. This can occur if coolant is leaking into the head. It could also be as simple as water entering the exhaust or carburetor after the engine was pressure-washed.
Blue Exhaust Smoke

If you are noticing blue smoke from the exhaust, it means your engine is burning oil due to an oil leak. This symptom could be the result of a leaking valve seal or a problem with a piston ring.

Blue smoke from the exhaust: Bluish smoke can indicate your car is burning oil during the combustion cycle. Burning oil smell: A thick burning oil smell could mean oil is seeping onto hot engine parts. Frequent low oil light warnings: Regular low oil warnings can indicate excessive oil consumption or a car burning oil.
If you notice that your engine overheats, the coolant temperature sensor could be the problem. At times, the coolant temperature switch may fail such that it starts transmitting hot signals permanently. This causes the computer to erroneously counterbalance the signal, thereby causing the engine to misfire or overheat.
Engine Could Overheat

When you don`t have enough coolant in your car, it could lead to your engine overheating. The coolant has a very important role in cooling your engine down, and when it doesn`t or can`t cool your engine down, it could seize.

Smoke often leaves car engines as a result of overheating. This can be caused by faulty wire casings, heated residues on the engine block and overheated liquids including oil, transmission fluid and brake fluid. There may also be a fault in your coolant system, or your engine may not have enough lubricant.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

After you sit with the car running, the car starts smoking and eventually starts shaking
ANSWER : Hi, thanks for writing in. It all depends where the smoke is coming from. If it is from the exhaust then your engine be running rich and starting to foul out the spark plugs. Have the computer tested to see if any codes are present that could indicate what is causing the smoke. If you see smoke from the engine compartment then you may be running the engine hot due to low airflow over the radiator. Have the cooling fan checked to make sure it is running. If it is running and the vehicle has the AC running and the blower is on or near high then you may be using more energy than the alternator can keep up with. This can cause the radiator fan to not turn as fast as it should and let the temperature to rise if idled for long periods. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Car started shaking. Cleaned carb and air filter. Now it starts, runs, dies, or starts and dies.
ANSWER : Hello. The stalling issues you are having may by caused by a variety of issues. Typically these symptoms can be blamed on fuel, spark, or air. Fuel and spark being the most common systems to fail. Starting with the air filter and cleaning the carburetor were good steps to start. You need to take a better look at the spark system. The spark wires can be tested to make sure the plugs are receiving the voltage that they need to be. You can also test the fuel system by spraying some starter fluid into the air intake. If this helps the engine start and run better than before, then you know you have a fuel delivery issue. This may include the fuel pump, fuel filter, injectors, or a clogged fuel line. The shaking is due to the improper combustion happening in the engine. This will be corrected when the engine is running properly. More testing is the only way to know definitively what the issue is.

My car will be starting perfect and when the gas tank gets lower it will start having problems .
ANSWER : Based on the information you gave, it sounds like a possible fuel starvation issue, caused by a partially blocked, in-tank fuel filter or a crack in the fuel pump housing. The remedy would be to replace the fuel pump assembly and filter. The overheating may be caused by several things, including a stuck thermostat, faulty water pump, or even a cracked head gasket. I suggest having a certified technician, like one from YourMechanic, inspect the relevant systems to pinpoint the cause of your vehicle’s hard starting issue and overheating problem.

Car intermittently won’t start
ANSWER : Hi there. An intermittent no start condition, can be difficult to diagnose. Replacing the fuel filter would not hurt anything, especially if it hasn’t been replaced in the last 30,000 miles. Diagnostic procedures should be performed, at the time of no start, to confirm whether there is a loss of fuel, of spark or both.

Assuming the Check Engine Light is not coming on, leads me to believe the ECM (engine control module)/computer is not recognizing the fault. There are many possibilities for a no start condition: a faulty ignition switch, fuel pump relay, fuel pump, ignition coil, ignition module, crankshaft position sensor, camshaft position sensor.

Replacing components without diagnoses can be expensive and time consuming without resolution. I recommend having your vehicle’s intermittent no start diagnosed and repaired by a certified technician, such as one from YourMechanic, so that this can be repaired correctly.

My car has been stalling then my gas pedal goes to the floor and wont go. I try to start it again, it’s smoking and car is shaking 2000 Oldsmobile Intrigue
ANSWER : Hello – your symptoms suggest that the head gasket(s) are blown on your engine, and coolant is leaking into the cylinders – hence the white smoke from the exhaust. Blown head gaskets can also cause misfire rough running, and low power levels. You don’t mention overheating, but an overheating event could be that cause of blown head gaskets, or just high mileage on this particular engine. I recommend a car is stalling inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and a cost estimate for repairs.

Car starts, shakes then Dies out within seconds!
ANSWER : Hi there. The dreaded rotten egg smell is caused by either a clutch that is damaged or the catalytic converter that needs to be replaced. I would recommend before you take your car to any repair facility or attempt any repairs; first have a professional mechanic come to your location and complete a car starts then dies inspection. This will allow them to pinpoint the source of your issues and recommend the right repairs.

car shakes when idle and accelerating
ANSWER : It is very possible that you have a valve cover gasket or spark plug tube seal leak on your vehicle. These type of leaks will allow oil to leak onto the spark plugs causing misfires. When the engine misfires due to oil getting on the spark plug, the engine oil will burn. Since oil and tires are both petroleum products, they will both smell similar when they are burning. I would recommend having an oil leak inspection performed by a qualified professional to determine if there is an oil leak. Consider YourMechanic as an Oil/Fluid leak inspection can be peformed at your home or office.