Turbo Steve
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Intake System Deposits Can Affect Performance and Emissions Control
Deposits have formed in engine intake systems (carburetors, fuel injectors - diesel / gas, intake manifold, ports, and valves) since the beginning of the spark-ignited internal combustion engine.
In today's modern engines, these deposits can affect engine performance and upset the emission control system designed by the automobile manufacturer.
Fuel Injector Deposits
Deposits that form in fuel injectors can restrict fuel flow and distort the spray pattern. This upsets the fuel-air ratio in individual cylinders since deposits do not form uniformly. When the air-fuel mixture in the engine cylinders becomes imbalanced, the oxygen sensor, which only responds to the average of all the cylinders, tries to correct the situation, but usually makes it worse. The result is a degrading of driveability as exhibited by rough idle, hesitation, and stumbling, a decrease in power, a reduction in fuel economy, and an increase in unburned hydrocarbons and carbon monoxide emissions.
Intake Valve Deposits
The formation of deposits on the tulip area of intake valves also can be detrimental. Under cold start conditions, the porous deposits can absorb enough fuel to cause first lean and then rich air-fuel mixtures which can degrade driveability. Intake valve deposits can cause unburned hydrocarbons, carbon monoxide, and oxides of nitrogen exhaust emissions to increase.
Furthermore, if the deposits are very heavy, power at maximum throttle can be reduced because the deposits restrict the flow of the air-fuel mixture into the cylinders.
The use of an aftermarket concentrated deposit control additive to remove the critical deposits can help restore the performance of an engine and the control of its emissions to the level designed by the auto manufacturer.
By Lew Gibbs http://www.chevron.com/prodserv/frame.html
------------------------------------------------------------------------------------------
Lew Gibbs works in Chevron Products Company's Product Engineering Department. Lew has authored numerous technical papers on diesel and gasoline deposit control. He is currently Chairman of the SAE Fuels & Lubes Technical Committee on Fuels and Chairman of the ASTM Gasoline and Oxygenated Gasoline Specifications Section.
[This message has been edited by Turbo Steve (edited February 13, 2000).]
Deposits have formed in engine intake systems (carburetors, fuel injectors - diesel / gas, intake manifold, ports, and valves) since the beginning of the spark-ignited internal combustion engine.
In today's modern engines, these deposits can affect engine performance and upset the emission control system designed by the automobile manufacturer.
Fuel Injector Deposits
Deposits that form in fuel injectors can restrict fuel flow and distort the spray pattern. This upsets the fuel-air ratio in individual cylinders since deposits do not form uniformly. When the air-fuel mixture in the engine cylinders becomes imbalanced, the oxygen sensor, which only responds to the average of all the cylinders, tries to correct the situation, but usually makes it worse. The result is a degrading of driveability as exhibited by rough idle, hesitation, and stumbling, a decrease in power, a reduction in fuel economy, and an increase in unburned hydrocarbons and carbon monoxide emissions.
Intake Valve Deposits
The formation of deposits on the tulip area of intake valves also can be detrimental. Under cold start conditions, the porous deposits can absorb enough fuel to cause first lean and then rich air-fuel mixtures which can degrade driveability. Intake valve deposits can cause unburned hydrocarbons, carbon monoxide, and oxides of nitrogen exhaust emissions to increase.
Furthermore, if the deposits are very heavy, power at maximum throttle can be reduced because the deposits restrict the flow of the air-fuel mixture into the cylinders.
The use of an aftermarket concentrated deposit control additive to remove the critical deposits can help restore the performance of an engine and the control of its emissions to the level designed by the auto manufacturer.
By Lew Gibbs http://www.chevron.com/prodserv/frame.html
------------------------------------------------------------------------------------------
Lew Gibbs works in Chevron Products Company's Product Engineering Department. Lew has authored numerous technical papers on diesel and gasoline deposit control. He is currently Chairman of the SAE Fuels & Lubes Technical Committee on Fuels and Chairman of the ASTM Gasoline and Oxygenated Gasoline Specifications Section.
[This message has been edited by Turbo Steve (edited February 13, 2000).]
