How To Remove Exhaust Stains From Car Paint?

Usually, Exhaust stains occur due to the mixing of some amount of air and fuel, which does not burn completely and thereafter producing soot (a byproduct of incomplete combustion) which later dries and gets deposited as getting exposed to air. In such scenarios, it becomes necessary to remove exhaust stains from car paint.

How Black Stains Occur Inside?

Black Stains is a very common problem found in four-wheel vehicles, as continuous ignition of the fuel inside the engine causes some part of the fuel to leave burnt and non-utilized, resulting in the car metal plate to cover with black soot.

Listed below are the reasons behind how black stains generally occurs:

1. Issue In The Carburetors:

Older cars are a great victim to this as the carburetors richen the emulsified oil because of which they didn’t get enough time to warm and prevent condensation. Due to this unreachable heating, water gets to mix with sulfur and acids thus leading to fast damage to the exhaust system. Production of black dusting occurs due to misfiring as well as due to misfuelling (shaking of the engine occurs). Also for an efficient output, the lambda sensors should be checked properly.

2. Issue With The Fuel Injectors:

Oil coming from somewhere maybe worn-out valve or piston rings as they are provided with sealed which may get broken down and oils leak from the valve stem. Misfuelling due to injectors could turn out to be a great problem to the engine and also other parts present inside of the car.

3. Defective Turbochargers:

Enormous burning of oil may lead to Turbochargers go fused, as the intercooler receives the oil, intakes the manifold, and then gets into the engine. In such a situation, it becomes a dangerous situation and cannot be stopped at the key.

3. Longer Duration By The Catalytic Converters:

Catalytic converters are not 100% efficient, because of which they take a long time to burn the extra fuel present until the oxygen sensors get warms up, and till then the engine runs in open-loop mode. As the sensors get warm-up, the engine runs in closed-loop mode.

If the soot deposited into the exhausts are thick in nature and also coating outside of it also, then a great probability is problem arisen due to fueling or timing of start/stop of the engine which needs to be fixed otherwise it would be difficult rather impossible to remove the exhaust stains and no other option would be left than to replace the metal body with a new one.

Methods To Remove Exhaust Stains From Car Paint?

Normally, when it comes to mind, then with the help of old torn-off cloth and with the help of any lubricant, we can wax them off. But there are some ideas which can help to clean them up and get rid of the exhaust stains from the car paint completely.

Some of them are listed below :

1. Use Baking Soda:

A mixture of baking soda and vinegar can be used as perfect lubrication to pull out the stains which have got solidified on the metal surface.

2. Use Of WD40:

We can also make use of WD-40, which can be seen doing the job with flying colors, can help in removing moisture and carbon residue from spark plugs and spark plug wires.

3. Use Of Paint Cleaners:

We can make use of a paint cleaner such as Scratch X, which helps in removing most of the junk, and then we need to clay it so as to avoid any traces or particles getting stuck.

4. Use Of Soap Water:

The black soot (which are none other than hydrocarbons) can be cleaned by making a foam of soap water, and a cloth that can remove them to a great extent, and then, we can restore the luster and shine with the help of metal polish.

5. Use Of Body Solvent:

In the same way, we can also make use of a body solvent or a wax cleaner (eg. Color X) or with the help of an adhesive remover – 3 M.

Modern Technology To Nullify Car Stains:

Presently, diesel engines that are manufactured have been provided with special filters to counter the production of stains. They have a regeneration mode in which the exhaust temperature is increased and correspondingly the filter pressure gets decreased and hence the trapped soot gets burnt off, thus helps a lot to remove exhaust stains from car paint and the exhaust pipes.

Side Effects Caused Due To Exhaust Stains:

Some of the issues occur in the background when exhaust stains get produced. They are described below:

1. Massive Noise In Engine:

It may lead to generate a large amount of engine while cold starting and accelerating the vehicle. May also produce a hissing or tapping sound if it leaks or have a manifest gasket.

2. Effect On Power And Acceleration:

The performance of the engine gets automatically affected as the exhaust starts showing problems. If the raw fuel starts overheating, the situation will worsen. This will enable us to accelerate quickly and consequently lead to worsening and leakage of the exhaust.

3. Effect On The Fuel Efficiency:

The engine power and the performance of the vehicle get decreased, leading to a decrease in the fuel efficiency also. Going wrong in the fuel pressure is a major noticeable thing to look upon. So in this scenario, we need to work harder and consume more fuel in order to function in the same way as it was before and we need it to.

 4. Issue In The Engine Bay:

This occurs usually due to failure of the gasket, leading to leakage in the engine wiring or any place present beside the hood which is made up of plastic. This starts the engine parts to burn which releases a burning smell same as that of the burning of the engine, which later also releases smoke, which should be taken some action before any dangerous fallout occurs.

5. Loosening Of The Exhaust Pipe:

If any part of the pipe breaks or drags in the ground, we should fix it immediately. It’s not a danger till it doesn’t break, but as it breaks into the ground and falls, the driver would be in a state of danger to control the vehicle.

Thus, the above points and the images corresponding to them explain enough why we should remove exhaust stains from car paint and other body parts where it sticks or attacks and starts damaging.


Hence, as a result, we come to the conclusion that it’s necessary to regularly check the pipes and body plates and remove exhaust stains from car paint if they start bulging on. We also need to be alert as it overstains and consecutively need to take the appropriate action so that it doesn’t permanently damage the body metal plate. Also, the exhaust pipe doesn’t get jammed due to continuous sticking of soot over it, for which it should be cleaned for the efficient functioning of the vehicle without any issues and damage.

For any questions outside of this article, do ask in the comment section below. We’ll get back to you.

Safe Driving

Thank You

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