Fuel Delivery Systems Are Getting Coked Up

Internal combustion (gasoline / diesel)  engines use heat and pressure to combust organic compounds (carbon products) to make power for driving our vehicles. In an ideal world, all the compounds would oxidize to water and carbon dioxide before coming out the tailpipe. However, that’s not always the case. More often than we’d like, fuel and oil vapors cause carbon build-up in engines. Sometimes this occurs on the tip of fuel injectors or in the combustion chamber. This carbon build-up can cause fuel injector function to falter or the spray pattern of the fuel injector to change. Leading to drivability issues, engine misfires (P0301, P0302, P0303, P0304, P0305, P0306), fuel mixture faults (P0170, P0171) and other associated fuel delivery issues.

Unfortunately, the organic soup that is gasoline or diesel fuel or engine oil is a mixture of molecules of different weight and complexity. Some of these molecules will surely burn cleanly and produce power, but others may not. Maybe there won’t be enough heat to break up and combust some of the heavier molecules; or not enough oxygen gets into the thickest part of the mixture; or engine oil gets into the mix and gums up the works – see our article on carboned up valves.

Previously, in port-injection engine designs, fuel injector nozzles were very susceptible to this gumming up. When fuel pressure was on the order of 1 or 2 bars, there just was not enough pressure to keep the injector tips clean. As the tips got deposits on them, fuel atomization suffered. This was in the days before direct injection; fuel was sprayed into the intake ports as intake air rushed past. So the shape of the injection cloud was not necessarily critical to the final result: the flame front in the combustion chamber did not depend on the injector nozzle pattern.

Why does fuel cause carbon build-ups in gasoline and diesel engines?

With the advent of direct injection (fuel injected directly into combustion chambers), two opposing conditions have taken hold. On the one hand, direct injection uses much higher fuel pressures, on the order of 5 to 10 bar. This means that injectors are much more likely to succeed in keeping their own tips clean.

But there is an opposing trend in direct injection engine: When heavy clogging hydrocarbons do find their way into the combustion chamber (as they inevitably will) and get deposited on injector tips, the effect on the injection cloud shape is far more significant than before. The engineers who design direct injection combustion chambers and injector tips calculate the shape of the injected fuel cloud for maximum efficiency of combustion. Using a principle called “stratification”, the density of fuel closest to the spark plug is designed to be the highest. Once the flame caused by spark begins to travel through the fuel, the flame front combusts far leaner fuel mixture farther away from the spark plug. But if injector tips are coked up or the injector cloud shape is otherwise distorted by carbon deposits, then the combustion flame front is also distorted, resulting in loss of engine efficiency and potentially a misfire.

Some Manufacturers Have Created A Solution

An additional factor is now becoming evident in current direct injection engine design. Ford and Toyota (and most likely other manufacturers) have been redesigning direct injection engines to be a mix of the old and new. In these dual-injector engines, the majority of fuel is still injected directly into the combustion chamber but a small amount is again injected into the intake ports in order to wash off the oil and carbon build-up on intake valves. This is a clever way to get around one of the major disadvantages of direct injection, but it means even more heavy organic molecules are imported into the combustion chambers with yet more opportunities to screw up those intricately designed injector ports.

Regular Treatment Using Pour-In Cleaners From ATS Will Clean These Carbon Deposits

Fuel Treatments to the rescue! In particular, pour-in fuel additives. ATS Carbon Clean, produces a specially blended chemical pour-in fuel treatment (505 CRF) that, when mixed with fuel, prevents injector tip deposits from forming. It also cleans off existing carbon from those tips. Once you have this solvent circulating in the engine, it keeps sludgy oil deposits and coke from forming on intake valve heads as well. Therefore the pour-in additive is recommended for both port-injection and direct injection engines, as well as the current dual-injector engine designs.

ATS Carbon Cleans 505 CRF chemical mixture is proven to remove carbon from; fuel injectors, induction ports, induction valves, and combustion chambers. Carbon deposits on the injectors can cause drivability problems and poor fuel mileage.

This advanced formula can clean carbon-coking from the port style injector and the direct style injector; increasing engine performance and fuel economy.

For internal combustion engine components

An advanced pour-in fuel treatment and cleaner that enhances gasoline and diesel fuel to remove carbon deposits from the internal combustion engine and engine components.

This chemical mixture is proven to remove carbon from; fuel injectors, induction ports, induction valves, and combustion chambers. Carbon deposits on the injectors can cause drivability problems and poor fuel mileage.

The 505 CRF advanced formula can clean coking from the port style injector and the direct style injector; increasing engine performance and fuel economy.

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