Black powder on back end?
03-15-2009, 06:11 AM
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I didn't notice this on my blue 528 but my white 550 gets a fine black powder on the back end that I am assuming is from the exhaust? My oil level is a couple clicks below full but no where near the point of adding oil.
Normal?
Normal?
03-15-2009, 06:25 AM
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Carbon Build-Up
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
03-15-2009, 10:04 AM
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Originally Posted by craigm1841' post='817213' date='Mar 15 2009, 09:25 AM
Carbon Build-Up
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
Then, engineer.
Then, I decided to compliment your mother and father on teaching you a ton of good stuff. Tell her to keep working on your spelling. LOL. Fantastic explanation, btw.
03-15-2009, 10:17 AM
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Originally Posted by z06bigbird' post='817348' date='Mar 15 2009, 02:04 PM
First, I thought technical writer.
Then, engineer.
Then, I decided to compliment your mother and father on teaching you a ton of good stuff. Tell her to keep working on your spelling. LOL. Fantastic explanation, btw.
Then, engineer.
Then, I decided to compliment your mother and father on teaching you a ton of good stuff. Tell her to keep working on your spelling. LOL. Fantastic explanation, btw.
03-15-2009, 10:23 AM
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My Ride: 2007 530i. Purchased 6/28/07. Titanium Silver Metallic, Black Dakota Leather, Dark Poplar Trim, Steptronic, Premium Package, Cold Weather Package, Bluetooth, Adaptive Control Xenons. 10/30/07 Added OEM 124s with 245/40/18 & 275/35/18 Michelin Pilot Sport A/S tires. Installed red Cal Covers� from BavAuto. 11/21/07 Added OEM all-weather floor mats (for winter, carpet in summer) and coat rack. 6/26/08 installed M5-style rear spoiler. 6/30/08 put on red reflectors. 8/22/08 Euro turn signal stickers applied. 3/20/09 Installed Shadowline Trim. 3/27/09 Added Matte Black Kidney Grilles from Trinity. 4/03/09 Installed Bimmian Shadow Matte Black 530i Badges. 4/04/09 Installed LED license plate lights from Trinity. 5/01/09 Installed Brabus Interior LED Kit and White Angel Eyes. 5/02/09 Put in Brabus 6K Fogs. 5/14/09 Removed charcoal filter. 5/15/09 Installed light smoke LED side marker lamps from Trinity. 5/21/09 Sprint Booster. 6/12/09 Painted exhaust tips flat black. 6/13/09 Pulled red Cal Covers and painted calipers low gloss black. 6/27/09 RPI Ram Air Scoop from Trinity. 8/15/09 Installed Brabus's silver invisibulbs front and rear. 9/24/09 Installed R-Dash license plate LEDs from Brabaus (John).
Originally Posted by SmithsonGA' post='817208' date='Mar 15 2009, 09:11 AM
I didn't notice this on my blue 528 but my white 550 gets a fine black powder on the back end that I am assuming is from the exhaust? My oil level is a couple clicks below full but no where near the point of adding oil.
Normal?
Normal?
03-15-2009, 04:44 PM
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My Ride: 2004 530i 6M
Originally Posted by craigm1841' post='817213' date='Mar 15 2009, 10:25 AM
Carbon Build-Up
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
Carbon is a natural byproduct of the combustion process and is vented through the exhaust system. It is normal for a thin layer of carbon to cover the parts of the engine and exhaust that come into contact with the combustion process or engine exhaust. Since the introduction of unleaded fuel, carbon deposits have been greatly reduced. Normally, carbon does not present a problem.
However, through the introduction of contaminents such as oil or overly rich air/fuel ratios, carbon build-up can become excessive and reduce engine performance and require costly service or repairs.
Driving habits can also impact the amount of carbon build up. Highway driving tends to cause the engine to get sufficiently hot so as to burn away some contaminents that would otherwise become deposits. Unfortunately, short trips tend to promote the build up of carbon deposits. Having said that, in general, there are two main causes of excessive carbon buildup; burned oil and overly rich air/fuel mixtures.
Oil-based carbon build-up occurs when piston rings become worn and oil is able to leak past the rings from the crankcase. Oil can also leak from valves into the combustion chamber. Typically oil-based deposits appear as dark black and have a gummy, tar-like consistency.
Carbon tends to coat any surface that may be exposed to either the combustion process or handle engine exhaust. It is often most evident on fuel injectors, engine valves and combustion chambers. Deposits also form on the throttle body, spark plugs, intake manifold as well as in the catalytic converter and oxygen sensors. If carbon buildup is present in the EGR passages, it is probably the result of oil leaking down the valve stems. An automobile that is burning oil will tend to emit exhaust that has a bluish tint and may be a little heavier than normal.
By contrast, fuel-based carbon build-up occurs when an engine burns an excessively rich air/fuel mixture. Too much fuel will tend to produce a relatively large amount of carbon waste that is not as thick as oil deposits but it is hard, dry and tougher to remove.
Causes of fuel-based deposits often include a computer fault, a bad or leaking fuel injector or other potential reasons that cause and excessive amount of fuel to be burned during the combustion process.
In general, carbon deposits can cause a drastic drop in both fuel economy and performance. Because so many automobiles on the road rely on computers and sensors for optimal engine performance, it is easy to see how carbon deposits can play havoc with modern engines. For example, most automobiles rely on an onboard computer to adjust the air/fuel ratio in accordance to the O2 readings for optimal performance. Because oxygen sensors are exposed to engine exhaust, it is easy to see how susptible they are to contamination from carbon-deposits. Incorrect oxygen sensor readings causes the computer to make performance adjustments based on incorrect data.
Particularly thick deposits also tends to increase engine compression simply because the carbon deposits take up more space inside the combustion chamber. Abnormally high compression may result in spark knock (detonation), particularly when driving under load or accelerating. In more extreme conditions, if carbon deposits are thick enough, the top of the piston may actually come into contact with the carbon-coated cylinder head or valves. When this happens, the sound resembles a hammer noise or like a rod bearing has gone bad.
Carbon build-up can also result in excessive auto emissions. Here's how: An excessively rich fuel mixture or burned oil can create a heavy carbon residue that coats the inside of the catalytic converter. If left unchecked, excessive carbon deposits can make the catalytic converter ineffective at burning residual fuel vapors (hydrocarbons). A sufficiently compromised catalytic converter will need to be replaced. In addition, if your state requires annual auto emissions testing, you may fail simply because your catalytic converter is unable to reduce your vehicle's auto emissions.
Here are a number of signs to keep an eye out for if you suspect carbon build-up:
-Engine pinging
-Hesitation
-Poor acceleration
-Spark knock
-Lack of power
-Carbon coated spark plug
-Repeated stalling in cold weather
-Thick, bluish exhaust
-Engine ping or a hammering sound
To treat carbon build-up there are off the shelf fuel addatives that tend to reduce or treat carbon build-up. In addition, there are more thorough carbon cleaning option available at most service facilities. Some of these solutions involve special chemicals, pumps and vacuum devices or blasting equipment to remove stubborn deposits.
If your engine has excessive carbon deposits, parts of the engine may need to be disassembled to do a thorough cleaning. Also, keep in mind that to do a thorough job, the intake manifold should also be removed to clean the carbon buildup from the inside of the manifold.
