Induction System Cleaning Method and Apparats Background of the Invention Field of the Invention This invention is in the field of service and maintenance methods and apparatus for automotive vehicles. Particularly, this invention is in the field of maintenance and service methods and apparatus for modem pollution-controlled passenger automobiles. In today's internal combustion gasoline engines, critical air/fuel mixtures, EGR flow rates, fuel injector flow rates, and fuel injector spray patterns necessitate a clean induction and combustion environment. All of these factors are necessary for proper vehicle performance and emissions behavior. Unburned hydrocarbons, oxides of nitrogen (NOx) and carbon monoxide all contribute to exhaust emissions. Unburned hydrocarbons are the major combustion by- products that contribute to the production of induction system deposits. Deposits in the induction system have a direct and negative effect on performance, fuel economy, and exhaust emissions.

Related Technologv Drivability problems with modem pollution-controlled automobiles, and with-other modem vehicles which have pollution-controlled gasoline engines, frequently relate to the induction system and/or EGR system of the vehicle's engine. These problems are often found to be caused by a dirty throttle body, a dirty intake manifold, dirty intake valves, a dirty combustion chamber and/or a partially or completely plugged EGR passageway in the intake manifold. The EGR passageway flows the exhaust gases back into the intake manifold, and is part of the pollution control system. Carbon build-up occurs in the EGR passageways and will eventually plug these passages. The result is the necessity of an expensive repair. This repair is frequently expensive because of the diagnosis problem, and because of the time required cleaning out the EGR passageway once the carbon deposits have been identified. To clean the carbon deposits, the automotive service technician must remove the EGR valve, remove the access plugs (if available) and manually dig the carbon out with a pick tool until the passage is completely clear.

The following are believed to be major contributors to formation of deposits in the induction system of an automotive internal combustion gasoline engine. The areas that are affected by each factor are listed below:

Fuel: oxidation, unburned or partially burned hydrocarbons, and heavier distillate fractions.

Fuel Additives: oxygenates added to improve the combustion process also tend to dissolve gums and varnish and move them to the hotter areas of the induction system, such as the intake valves and combustion chamber.

Positive Crankcase Ventilation (PCV): combustion by-products are recirculated into the induction system.

Exhaust Gas Recirculation (EGR): the EGR passageway flows the exhaust gases back into the intake manifold. These gases can be very reactive and promote formation of deposits that are both hard and difficult to remove.

Fuel System Design: location of injectors and valves adjacent to high temperatures, leading to "coking"of deposits on the injectors, valves, and combustion chamber.

Driving Conditions: exceptionally hot or cold weather driving, trailer towing, short trips, stop and go driving, all fail to allow the engine to operate under optimum operating conditions. In addition, any type of driving that generates higher than normal engine temperatures will contribute to deposit formation.

The factors set out above are believed to cause induction system deposits in the following areas: Throttle Body/Plate: deposits around the throttle plate could prevent the plate from seating properly at idle. This can cause the throttle position sensor (TPS) to give a false signal to the electronic control unit or module (ECU or ECM), which signals the ECU for idle, acceleration, and wide open throttle. These deposits can cause rough idle, stalling and hesitation.

Intake Manifold/Intake Valves: deposits in the intake manifold and on the intake valves can absorb fuel before it reaches the combustion chamber. The result is a lean condition, which is detected by the oxygen sensor. Based on the input of the oxygen sensor the ECU signals the injectors to stay open longer to richen the air/fuel mixture. This cycle continues until the system is clean and results in a loss of performance and an increase in exhaust emissions. Hesitation, cold start problems and stalling can also result.

EGR Passageway (s): deposits in the Exhaust Gas Recirculation (EGR) passageway (s) can completely plug one or more cylinders from receiving EGR flow. The result is an increase in NOx emissions and detonation (pinging) at cruise or light throttle acceleration.

Fuel Injectors: deposits on the tip of the injector can disrupt the uniform atomization of the fuel. Some injectors may be fouled while others may be relatively clean. The result is some cylinders running too lean and some others running too rich.

Combustion Chamber: deposits in the combustion chamber decrease the overall volume, resulting in an increase of the compression ratio. This can cause octane requirement increase (ORI), which means that the engine may knock or detonate (ping) because of compression caused combustion unless a higher octane grade of gasoline is used.

These deposits can also create hot spots in the combustion chamber that can cause the air/fuel mixture to pre-ignite before the park. The result is a loss of power and out of balance cylinder activity.

Two common expedients used to address these many problem areas are the use of gasoline additives added to the fuel tank. These are so-called carburetor or fuel injector cleaners, and simply do not completely clean the induction system of an automobile engine.

The other expedient is the carburetor or throttle body spray cleaner that is sprayed from outside into the induction opening of a carburetor or throttle body (preferably while the engine is running) in an attempt to remove the deposits from this carburetor or throttle body. Again, such expedients do not clean the entire induction system of an automobile engine.

Summary of the Invention Until now, there has been no method to completely and simultaneously service the various components of the induction system and EGR system of a modem pollution-controlled gasoline engine in an automobile.

Accordingly, an objective of the present invention is to avoid or reduce the effect of one or more of the shortcomings of the related conventional technology.

A particular objective of the present invention is to provide a method to simultaneously clean both the induction system and the EGR system of a gasoline automotive engine.

Yet another object of the present invention is to provide an apparatus for use in carrying out the method of the present invention.

Still another object for this invention is to provide an air intake cleaner tool which is introduced in the air stream traversing the throttle body of an automotive engine and flowing to the combustion chambers of the engine, and which tool is effective to introduce into this air stream an atomized liquid cleaner effective to remove or reduce deposits on the throttle body, intake tract, intake valves, and combustion chambers of the engine.

Another object is to provide an apparatus for introducing a flow of cleaner fluid into the EGR passages of an engine simultaneously with the introduction of the cleaner fluid via the induction tract.

Other objects, features, and advantages of the present invention will be apparent to those skilled in the art from a consideration of the following detailed description of a preferred

exemplary embodiment thereof taken in conjunction with the associated figures which will first be described briefly.

Brief Description of the Drawing Figures Figure 1 provides a diagrammatic view of an automotive engine having its induction system cleaned using an apparatus and method according to the present invention; Figure 2 provides a diagrammatic view of an automotive engine having its induction and exhaust gas recirculation (EGR) systems cleaned simultaneously using an alternative apparatus and method according to the present method; Figure 3 provides a side elevation view, partially in cross section of a portion of the apparatus seen in Figure 2; and Figure 4 presents an illustrated tabulation of component parts used with differing automobiles to complete the apparatus and practice the method seen in Figure 2.

DETAILED DESCRIPTION OF EXEMPLARY PREFERRED EMBODIMENTS OF THE INVENTION While the present invention may be embodied in many different forms, disclosed herein are two specific exemplary embodiments that illustrate and explain the principles of the invention.

In conjunction with the description of these embodiments, a method of cleaning the induction system, or the induction system and EGR system simultaneously by use of the present invention is described. It should be emphasized that the present invention is not limited to the specific embodiments illustrated, but is capable of considerable modification and alteration, which will suggest themselves to those ordinarily skilled in the pertinent arts, to whom this description and disclosure is directed.

Vacuum Powered Cleaning Referring first to Figure 1, an automotive engine 10 includes a piston 12 and cylinder 14, which are merely representative possibly of plural such pistons and cylinders the engine 10 will ordinarily have. The engine 10 includes an induction system 16 having an air filter 18, a mass air flow sensor 20, a throttle body 22, an intake plenum 24, a plurality of intake runners or conduits 26 (only one of which is seen in Figure 1), with each of the intake runners 26 communicating with an intake port 28 and intake valve 30 of the engine. Those ordinarily skilled in the pertinent arts

will understand that the engine 10 includes at least one intake runner and intake valve for each of the cylinders of the engine.

The intake valves 30 control admission of air and fuel to a combustion chamber 32 cooperatively defined by the piston 12 and cylinder 14. An exhaust valve 34 similarly controls outflow of exhaust products (indicated by the character"e"on Figure 1) from the chamber 32 via an exhaust port 36 and exhaust manifold 38 leading to an exhaust pipe 40. The exhaust products "e"flow past an oxygen sensor 42 which detects and electronically reports the quality of combustion carried out in the engine 10. When the engine 10 is running, a partial vacuum is maintained by the engine in the area extending from the throttle body 22 through the plenum 24, runners 26, and to the intake ports 28. This vacuum is caused by the expansion of chamber 32 while valve 30 is opened, and draws ambient air into the chamber 32 for combustion.

In order to provide fuel to sustain the combustion in chamber 32, the engine is associated with a fuel tank 44 containing a supply of fuel 46, which is most preferably gasoline. This gasoline 46 is moved under pressure provided by a pump 48 through a fuel filter 50 and to a fuel injection nozzle 52. As is illustrated by Figure 1, this fuel injection nozzle 52 directs a spray of gasoline into the chamber 32 past the intake valve 30 when this valve is opened. Excess fuel is returned via a fuel pressure regulator 54 to the fuel tank 44.

As pointed out above, the engine 10 may be subject to drivability problems because of the accumulation of undesirable deposits in the induction system 16, and also in an exhaust gas recirculation (EGR) system 56. Those ordinarily skilled in the pertinent arts will know that the EGR system 56 includes an exhaust gas recirculation valve (not shown in the drawing Figures) which normally controls the flow of exhaust gasses from manifold 38 to the intake plenum 24 dependent upon operating conditions of the engine 10. This EGR flow is used to help control exhaust emissions from the engine 10 under certain operating conditions. The EGR valve is ordinarily mounted at or in association with the plenum 24 and has connection into the plenum at the location indicated by the arrowed numeral 56. As is seen in Figure 1, the EGR valve has been removed or disconnected and a plate-like fitting 58 has been attached to the plenum 24 in order to allow connection of a conduit 60 leading to an atomizing nozzle, indicated with arrowed numeral 62. The conduit 60 leads to the atomizing nozzle 62 from a container 64 of liquid cleaner. The container 64 is provided with a valve 66 which controls the flow of liquid cleaner from the container 64 into the EGR passages of the EGR system 56. When the engine 10 is operating, the manifold vacuum of this engine is sufficient to cause this liquid cleaner flow when the valve 66 is opened.

Similarly, an atomizing nozzle 68 provides liquid cleaner from container 64 into the intake plenum 24 via a conduit 70 leading from a T-connection with the conduit 60. Again, when the engine 10 is operating, the liquid cleaner from container 64 is atomized into the plenum 24, and flows to the combustion chamber 32 via the intake ports 28.

To carry out the vacuum powered cleaning of the engine 10, most preferably (but optionally) a cleaner for the fuel injectors and other"fuel wetted"portions of the induction system 16 is added to the tank 44. A first liquid cleaner is provided in container 64, which cleaner is effective to clean the deposits from the EGR passages, and is also effective to clean valves 30, injectors 52, and combustion chambers 32. This liquid cleaner is first introduced via the atomizer nozzle 62 via the passages of the EGR system 56, and is effective to soften deposits in and to clean the passages of the EGR system. For this portion of the process, the atomizer 68 will not be supplied with cleaner. After the first cleaner is introduced, the engine is allowed a"soaking"period during which the first cleaner further softens deposits in the EGR system 56. Next, a second cleaner is added to container 64 (or this container is replaced by another) which second cleaner is effective to clean both the intake manifold 24, and to flush softened deposits from the passages of the EGR system 56. For this phase of the process, both atomizer nozzles 62 and 68 are used simultaneously to introduce the second cleaner. This method is effective to remove deposits from both the induction system and from the EGR system of the engine 10 simultaneously, and is powered by engine vacuum while the engine 10 is running.

Pressurized Cleaning Referring now to Figure 2, an alternative pressurized method of cleaning an engine is depicted. This method and the apparatus used to practice is has many features in common with the embodiment depicted by Figure 1. Thus, features of Figure 2 which are the same as or which are analogous in structure of function to features depicted and described above with reference to Figure 1, are indicated on Figure 2 with the same numeral used above and increased by one- hundred (100). Viewing now Figure 2, an automotive engine 110 includes a piston 112 and cylinder 114. The engine 110 includes an induction system 116 having an air filter 118, a mass air flow sensor 120, a throttle body 122, an intake plenum 124, a plurality of intake runners 126, with each of the intake runners 126 communicating with an intake port 128 and intake valve 130 of the engine. The valves 130 control admission of air and fuel to a combustion chamber 132. An exhaust valve 134 similarly controls outflow of exhaust products"e"from the chamber 132 via an exhaust port 136 and exhaust manifold 138. The manifold 138 leads to an exhaust pipe 140. The

exhaust products"e"flow past an oxygen sensor 142. The engine 110 is also associated with a fuel tank 144 containing a supply of fuel 146. The engine 110 has a fuel pump 148, a fuel filter 150, and a fuel injection nozzle 152. Excess fuel is returned to the tank 144 via fuel pressure regulator 154.

As is seen in Figure 2, the EGR valve has in this case also been removed or disconnected and a plate-like fitting 158 has been attached to the plenum 124 in order to allow connection of a conduit 160 leading to an atomizing nozzle, indicated with arrowed numeral 162. The conduit 160 leads to the atomizing nozzle 162 from a container 164 of liquid cleaner. The container 164 is provided in this case with a valve 166 which controls the flow of pressurized air from a source (indicated with the arrowed numeral 74). As an example only, the source 74 may include or be provided by a connection to a source of shop air at the location where the engine 110 is being serviced.

Further attention to Figure 2 will reveal that the conduit 160 has interposed in it a safety shutoff valve 160a, which is operated by engine vacuum, and which controls the flow of cleaning fluid from the container 164 regardless of whether the valve 166 is opened or closed. The safety shutoff valve 160a is normally closed, is self-closing, and is opened by engine vacuum. This valve 160a is connected by a vacuum line 160b to a fitting 160c communicating with a source of engine vacuum. In this case, the fitting 160c communicates with an intake runner 126 or with the plenum chamber 124 downstream of the throttle body 122. The result is that liquid cleaning fluid can flow from the container 164 to the engine 110 only when this engine is running and providing intake manifold vacuum. Thus, if during a service procedure the engine 110 should stop running, then intake manifold vacuum will cease and the flow of liquid cleaning fluid from container 164 into the engine 110 is also immediately stopped by self-closing action of the valve 160a. This automatic shut off of the flow of liquid cleaning fluid into the engine 110 insures that the engine 110 is protected against hydraulic lock. That is, a sufficient flow of liquid cleaning fluid from container 164 cannot flow into the engine 110 while this engine is not running such that this liquid might accumulate in a combustion chamber and damage the engine when an attempt is made to restart the engine.

In the method illustrated by Figure 2, an atomizing assembly 76 has been interposed into the induction system 16 of the engine 10 between the air cleaner 118 and throttle body 122.

Viewing Figure 3, it is seen that this atomizer assembly 76 includes a tubular body 78 which at one end defines a stepped outer surface portion, indicated with the numeral 80. The surface 80 in this case provides two differing diameters of surfaces 80a and 80b to which the intake conduit from the air cleaner 118 and/or mass air flow sensor 120 may be connected. This conduit is

indicated on Figure 2 with the numeral 182, and it carries a band clamp 182a securing the conduit to the atomizer assembly 76. Thus, combustion air flow to the engine 110 (indicated on Figure 2 by the arrowed characters"a") passes through the atomizer assembly 76. At its opposite end, the atomizer assembly 76 defines a"stepped cone"surface 84. That is, the surface 84 provides a conical surface portion indicated with the numeral 84a, and a slightly larger diameter and cylindrical step portion 84b. In the service situation illustrated in Figure 2, the engine 110 has a throttle body 122 with an inner diameter accepting the conical surface 84a. Other engines in other vehicles may engage the surface 84a at different locations. Still other engines may have a throttle body with an intake diameter sufficient to engage upon the step surface 84b. Still other engines may require an adapter (not shown) to be used in order to provide good air flow connection to the throttle body. In these latter cases, the adapter may engage the atomizer assembly 76 at the step surface 84b.

Atomizer assembly 76 includes a connection (i. e., a hose barb) to conduit 170 leading from container 164. Liquid which flows to the atomizer assembly 76 via conduit 170 is conducted along an internal passage (not seen in Figure 2) to a tubular extension 86, and to an atomizer nozzle 88 suspended in the air stream"a".

In order to carry out the pressurized cleaning of the engine 110, a cleaner for the fuel injectors and other"fuel wetted"portions of the induction system 116 is again most preferably (but optionally) added to the tank 144. The first liquid cleaner is first provided in container 164 and is first introduced via the atomizer nozzle 162 along the passages of the EGR system 156. Again, this first liquid cleaner is effective to soften deposits in and to clean the passages of the EGR system. For this portion of the process, the atomizer assembly 76 will not be supplied with cleaner. After the first cleaner is introduced, the engine is allowed a"soaking" period during which the first cleaner further softens deposits in the EGR system 156. Next, the second cleaner is added to container 164 (or again, this container may be replaced by another) which second cleaner is effective to clean the throttle body 122, as well as the intake manifold 124, runners 126, and intake ports 128. This cleaner also has a beneficial effect in cleaning the intake valves 130 and combustion chambers 132. It also further softens and flushes softened deposits from the passages of the EGR system 156. For this phase of the process, both the atomizer nozzle 162 and the atomizer assembly 176 are employed to simultaneously introduce the second cleaner to the engine 110. This method is effective to simultaneously remove deposits from both the induction system and from the EGR system of the engine 110.

Turning now to Figure 4, a few examples of various EGR adapter plates 58 (and 158, for these are the same adapter plates) for various automobiles and the engines of these automobiles

are depicted. These examples are not exhaustive nor are they limiting of the present invention.

Rather, the examples provided by Figure 4 are set out here to provide disclosure of adapter plates which may be used to complete the apparatus of the present invention for use on a number of conventional and common vehicles. Additional and different adapter plates may be used with and to complete the apparatus of the present invention. Those ordinarily skilled in the pertinent arts will doubtless have many such alternatives suggest themselves. Importantly, each of the adapter plates 58 seen in Figure 4 (designated 58a through 58j) is designed and configured to temporarily replace the EGR valve of a particular vehicle during vacuum powered or pressurized cleaning as described above, and to allow either a vacuum powered atomizer nozzle 62, or 68 (as is seen in Figure 1), or a pressurized atomizer nozzle 168 (as is seen in Figure 2), to be employed with the adapter plate. For this reason, each of the adapter plates 58a-58j seen in Figure 4 includes an aperture 59, with all of the apertures 59 being configured the same, and which will sealingly receive any one of the atomizer nozzles 62,68, or 168. The atomizer nozzle which is received into the aperture 59 of a particular adapter plate 58 is aligned and positioned such that the atomizer nozzle discharges atomized cleaning liquid into the EGR passage (or passages) of the particular engine for which the adapter plate is intended. Examples of these various vehicle and engine combinations are shown in the left-hand column of Figure 4. Once the cleaning process as described herein is completed, the adapter plates 58 are removed from the engine, the EGR valve is replaced, and other connections of the engine's pollution control system are restored. The adapter plates 58 are durable and reusable so that many vehicles may be serviced using a single set of these plates.

Those skilled in the pertinent arts will further appreciate that the present invention may be embodied in other specific forms without departing from the spirit or central attributes thereof.

Because the foregoing description of the present invention discloses only particularly preferred exemplary embodiments of the invention, it is to be understood that other variations are recognized as being within the scope of the present invention. Accordingly, the present invention is not limited to the particular embodiment which has been described in detail herein. Rather, reference should be made to the appended claims to define the scope and content of the present invention.