When I start the car it idles ok when cold and when getting warm it start to idles rough and smoke coming from exhaust,when I rev the car it backfires from exhaust,and I can smell petrol from the exhaust.After switching it of and checking the oil,the oil is full of petrol and oil is very light because of petrol mixing with it.i have changed injectors thinking that it inject too much petrol but nothing has changed.
My car has an automatic transmission.
Hello. If your oil is being mixed with fuel then you are either getting too much fuel into the engine or you have a serious internal engine issue. Most of the time this is caused by worn out piston rings. If the rings are worn out then the fuel will bypass the rings and enter the oiling system. I usually do a compression test to verify if this is possible. If the compression is fine then I suspect that the computer is commanding too much fuel into the engine which is usually caused by a failure in the computer or an issue with one of the sensors. I use a scan tool to check the sensors first and then test the computer from there if needs be. If you want to have this fuel in the oil checked, consider getting some help from YourMechanic, as a certified mechanic can come to your home or office to [diagnose why there is too much fuel entering the engine] https://www.yourmechanic.com/services/smoke-from-engine-or-exhaust-inspection
How to Identify and Fix Common car Problems ?
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On the other end of the spectrum, a bad fuel pump, vacuum leak, or clogged fuel injectors could cause an air-fuel ratio that`s too lean; that is, it has too much air and not enough fuel. Though this is the opposite problem, it can also cause a backfire as vapor escapes into the exhaust and combusts there.
However, the main cause is through a process called blow-by. This occurs because most seals are not perfect (nor are the cylinders perfectly rounded), or there is an opening through the cylinder crosshatches, and this causes the migration of fuel and exhaust gases into the areas where the oil is used.
Keep your foot on the gas pedal as it starts up. Once it`s up, press the accelerator down as hard as you can. This should cause the car to backfire.
If too much fuel is added to the engine, it may not all burn up before the exhaust valves open — letting unburned gasoline into the red-hot exhaust headers, where it can combust and lead to a backfire. Too much fuel could be getting into your engine due to damaged and leaking fuel injectors or bad engine sensors.
The spark inside the chamber may not burn up all the fuel, allowing a little extra gasoline vapor to enter the exhaust, and lead to a backfire. This can be caused by a faulty mass airflow sensor or a clogged engine air filter “choking” the engine and not allowing enough oxygen to flow into it.
Failure to do this could result in lack of power, unburnt fuel, damaging the injector and in some cases excessive smoke. While replacing fuel injector seals is not a routine maintenance procedure, most manufacturers do have a suggested replacement interval for them, to prevent the possibility of them failing.
Another possible cause of your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.
The reason for backfiring being common on a turbo vehicle is the fact that for all that extra air a turbo pushes into the engine it must also get more fuel. When your foot lets off the gas there is more raw unburnt fuel coming out of the cylinder head and flash igniting which causes the sound of a backfire.
Such a mixture could be caused by low fuel pressure due to a failing fuel pump, a clogged fuel filter or clogged fuel injectors. When a lean mixture combusts, it burns more slowly, meaning there will still be some air and fuel that isn`t used up when the exhaust valves open — leading to a backfire.
One common cause of car popping sounds is a loose exhaust pipe or muffler. If you hear popping when accelerating, it`s likely due to an issue with your fuel mixture or ignition timing. If you hear the popping sound at all times, it could be coming from your suspension or tires.
The most common thing for popping in the exhaust is excess air or too little fuel. this means that it is burning too hot in the combustion chamber, therefore the exhaust is hotter than it should be and is still burning fuel when it enters the exhaust system.
There`s a variety of factors that can cause your car to backfire, but the most common ones are having a poor air to fuel ratio, a misfiring spark plug, or good old-fashioned bad timing.
Engine misfires have a very distinct sound that can make them easier to diagnose than other car problems. Popping, sneezing, or banging sounds coming from the exhaust are a sign of a misfire. This sound comes from the unburnt fuel leaving the cylinder that combusts through the exhaust system.
There are many reasons for faulty fuel injectors but the three most common issues are clogging in your car`s fuel injectors, leaky and dirty injectors. You should remove the fuel injectors and clean them up before putting them back in for your car to function optimally.
Typically, a car delivers a subtle rumble when at idle. If you notice that the sound has gone from low to a rough and unpleasant noise, it may be a sign of bad fuel injectors.
Common problems include stalling after you have pressed the accelerator, struggling to accelerate and poor fuel economy. Most of these problems occur due to inadequate air to fuel ratio. Also, any delay could lead to overheating and the engine could stall.
The Dipstick Smells Like Gas This is an obvious sign that gasoline has leaked into your oil pan, especially if you take this test a step further to see how fast the oil falls off the dipstick. If it drips off rather easily, then you have gas mixed with your oil.
If there is oil in your coolant or vice versa, it generally means there is a failure in one or more of your engine`s gaskets or seals. Your engine is designed so that there is one system that controls engine oil to lubricate your vehicle and another that manages coolant to keep your car from overheating.
Yes, if you`re using the generally accepted definition of a combustion event that occurs in the exhaust manifold instead of the engine cylinder. The turbo is using the exhaust gasses from the engine to spin a compressor, so it`s usually located just downstream of the exhaust manifold.
Backfiring. When your vehicle starts to backfire, a bad ignition coil could be the culprit. A vehicle makes a loud bang sound when unused fuel in the combustion cylinders explodes, causing black smoke to emerge from the exhaust pipe and the strong smell of gas.
Hence, the turbocharger surging is a result of various engine parts not performing in sync. A worn-out engine cylinder or fuel system may lead to problems in the engine and the turbocharger. This will result in less airflow to the compressor against the higher back pressure, making the compressor surge.
A defective positive crankcase ventilation (PCV) valve or a malfunctioning exhaust gas recirculation (EGR) valve also can cause a backfire.
The problem with the Holley power valve is that it is the most sensitive circuit in the carburetor. The little rubber diaphragm has a tendency to tear or just plain fail at usually the most inopportune times. It is especially vulnerable to engine backfires.
