I have gray smoke coming out of my tailpipe but it’s not heavy smoke and my car check engine light is orange​ my car shut off

I just got a 2004 Kia optima I got a oil change and a new radiator done on it. But I noticed gray light smoke coming from my tailpipe and my check engine light is always on it's orange. So when i was driving my car to a shop i turned around cause of the little gray smoke and my car felt like it was going to cut off so as soon as I got home the car cut off so I tried to cut it on 2 times it wouldn't start so I kelp it off for a little and then started again it crank up fine but I didn't drive it I just turned it back off but the check engine orange light was still on
Experienced mechanics share their insights in answering this question :
You did not mention why the radiator was replaced but I think your engine was overheated causing the head gasket to go bad. This would cause the white smoke out of the tail pipe and an engine misfire and overheating can cause the check engine light to be on. I recommend having the engine checked for leaking head gasket and scan the computer for codes.

How to Identify and Fix Common car Problems ?

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If the smoke from the exhaust pipe is either grey or bluish-tinged, it generally means that your engine is burning oil inside the combustion chamber. Burning oil could be due to a number of causes, from leaky valve seals to bad piston rings.
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.
At times, black smoke can be an indicator that a manmade material is burning such as tires, vehicles or a structure. As a general rule, the darker the smoke, the more volatile the fire is. Grey smoke can indicate that the fire is slowing down and running out of materials to burn.
Thick white smoke coming out of the exhaust typically indicates a blown head gasket, a crack in the head, or a crack in the engine block. Cracks and bad gaskets allow the fluid to travel to places it shouldn`t be. If it travels, then the problems begin.
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.

White exhaust smoke

If your exhaust smoke is white, this is a reason for concern in a diesel engine vehicle. White exhaust smoke means fuel is not burning properly. This could mean: The engine is too cold.

To fix blue or gray smoke: The easy way is to add a bottle of Motor Honey Oil Treatment to your motor oil with each oil change. It`s specially designed to reduce oil burning and stop smoky exhausts. The hard way is an engine overhaul, which is about a hundred times more expensive and a thousand times more work.
If bluey-grey smoke leaves your exhaust while your vehicle is accelerating, this is usually the tell-tale sign of damaged piston rings. The parts are found in cylinders and can leak oil when they lose their seal. The fault is uncommon and will need the help of a professional to fix.
Thick white smoke pouring from the exhaust is usually due to a crack in the cylinder head, engine block or head gasket. This is caused by constant temperature fluctuations and a consistently overheating engine due to low coolant levels.
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.
White smoke is a result of unburned fuel particles passing through your car`s combustion chamber and out of the exhaust pipe. As previously mentioned, white smoke is related to lower temperatures in the combustion chamber. When the chamber isn`t hot enough, some fuel particles fail to ignite.
White Smoke:

White smoke coming from the exhaust usually points to one point of failure: the injectors. Usually, white smoke indicates that the diesel fuel is not burning correctly.

One of the telltale symptoms of a blown head gasket is white smoke from the exhaust. It`s important that the smoke is white because blue or black smoke can indicate a rich running engine or an engine that is burning oil.
There is an easy way to find out if your engine`s head gasket has blown. Simply check under the oil filler cap. If the gasket is not damaged, the inside of the oil cap will be mostly dry. If you discover a milky brownish-yellow substance that is similar to the thickness of a milkshake, you probably have a gasket leak.
If a bad oxygen sensor disrupts the air to fuel ratio mixture, or too much fuel is injected into the engine, your vehicle`s gas mileage will be reduced. This excess fuel in the engine can produce a sulfuric, rotten egg smell, and may even produce black smoke from the exhaust.
If you don`t get it fixed soon, you will have damage to your catalytic converter(s). A clogged converter can lead to expensive replacement work. So if you see white smoke coming from your tailpipe, bring your vehicle into a shop right away.
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.

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.
The carbon chucks could clog your EGR valve, which will result in loss of power, fuel inefficiency and emission of black smoke from your exhaust.
Other signs that your oil is leaking into your fuel and burning are misfiring spark plugs and rough vibrations while idling, but the blue smoke is an unmistakable, tell-tale sign of this issue.
Blue smoke is another indicator that there is a mechanical problem with your car. A burning smell often accompanied by blue smoke coming from the exhaust indicates that engine oil is burning. Engine oil is responsible for lubricating vital moving parts of your engine, ensuring that they do not get damaged or overheat.
Blown Head Gasket

Blown head gaskets are famous for leaking excess oil onto hot surfaces. Blue smoke indicates that lubricating oil has made its way into the hot exhaust system or other connecting engine parts.

The most common answer to, “Why is my car smoking but not overheating?” is that there`s a type of fluid that`s landed on the engine. This can be motor oil, fuel, transmission fluid, coolant, or even condensation. It can cause your engine to smoke because it`s burning off that fluid from the engine.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

I have gray smoke coming out of my tailpipe but it’s not heavy smoke and my car check engine light is orange​ my car shut off
ANSWER : You did not mention why the radiator was replaced but I think your engine was overheated causing the head gasket to go bad. This would cause the white smoke out of the tail pipe and an engine misfire and overheating can cause the check engine light to be on. I recommend having the engine checked for leaking head gasket and scan the computer for codes.

My car stalls at times, yesterday the car shut off at a red light. I turned car off then back on now engine light is on.
ANSWER : This may be a result of a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. Since this valve is controlled by the vehicle’s computer, it will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your idle air control valve.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

Car goes into limp mode when the check engine light and VSA light comes on
ANSWER : The lights that you have on and the vehicle going into fail safe mode is an indication you have a major system failure that will require computer to be tested for codes first. There are many possible codes it can be so the additional testing will be needed to isolate the cause of the problem.

Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.

Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.

To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.

Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?
ANSWER : Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the wires to the oil pressure sensor and make sure that they are connected and not broken. If everything looks good, then the oil pressure sensor may have failed. Plus, check the computer for codes and see what is stored. This will lead you to the part that could have failed. I recommend replacing the oil pressure sensor then checking to see if the lights will go out. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with the warning lights that came on.

Traction light/reduced engine power and check engine light coming on
ANSWER : Hello. From what you describe, it would appear that your vehicle may be experiencing some sort of intermittent wiring or sensor issue. If the problem occurred again after driving over a bump, then it may be possible that a damaged or loose wire is shorting or having contact issues. A common issue that can cause stalling is a faulty crank position sensor or wiring. I would carefully examine the engine for any loose or damaged wires. If the Check Engine Light comes back on, I would recommend having the trouble codes scanned before resetting the computer.

Engine Light and AT light. Car goes into limp mode
ANSWER : Hello. Most of the time this is the result of a transmission failure. It is common for this transmission to have internal pressure problem which will cause these codes. It can also be a voltage problem so I always check that first. I check the voltage going to the transmission and if it is too low I repair that issue which is commonly the ignition switch. If the voltage is fine, then the transmission pressures need to be checked and it will more than likely need to be replaced. I would have a transmission specialist look into this.