P/N A5073-SNOS THROTTLE POSITION CONTROLLED PROGRESSIVE NITROUS CONTROLLER INSTALLATION INSTRUCTIONS Kit Number 15835NOS OWNER S MANUAL NOTICE: Installation of Nitrous Oxide Systems Inc. products signifies that you have read this document and agreed to the terms stated within. It is the purchaser s responsibility to follow all installation instruction guidelines and safety procedures supplied with the product as it is received by the purchaser to determine the compatibility of the product with the vehicle or the device the purchaser intends to install the product on. Nitrous Oxide Systems Inc. assumes no responsibility for damages occurring from accident, misuse, abuse, improper installation, improper operation, lack of reasonable care, or all previously stated reasons resulting from incompatibility with other manufacturers products. Nitrous Oxide Systems Inc. assumes no responsibility or liability for damages incurred by the use of products manufactured or sold by Nitrous Oxide Systems Inc. on vehicles used for competition or racing. Nitrous Oxide Systems Inc. neither recommends nor condones the use of products manufactured or sold by Nitrous Oxide Systems Inc. on vehicles, which may be driven on public roads or highways, and assumes no responsibility for damages incurred by such use. NOS nitrous oxide is legal for use in most states when used in accordance with state and local traffic laws. NOS does not recommend or condone the use of its products in illegal racing activities. HAZARDS DEFINED This manual presents step-by-step instructions that describe the process of installing your NOS Nitrous Oxide Injection System. These procedures provide a framework for installation and operation of this kit. Parts are referenced by name and number to avoid confusion. Within the instructions, you are advised of potential hazards, pitfalls, and problems to avoid. The following examples explain the various hazard levels: WARNING! Failure to comply with instructions may result in injury or death. CAUTION! Failure to comply with instructions may result in damage to equipment. NOTE: This information is important, needs to be emphasized, and is set apart from the rest of the text. HINT: These special instructions provide a handy work tip.
NITROUS OXIDE INJECTION SYSTEM SAFETY TIPS WARNINGS Do not attempt to start the engine if the nitrous has been injected while the engine was not running. Disconnect the coil wire and turn the engine over with the throttle wide open for several revolutions before attempting to start. Failure to do so can result in extreme engine damage. Never permit oil, grease, or any other readily combustible substances to come in contact with cylinders, valves, solenoids, hoses, and fittings. Oil and certain gases (such as oxygen and nitrous oxide) may combine to produce a highly flammable condition. Never interchange nitrous and fuel solenoids. Failure to follow these simple instructions can result in extreme engine damage and/or personal injury. Never drop or violently strike the bottle. Doing so may result in an explosive bottle failure. Never change pressure settings of safety relief valve on the nitrous bottle valve. Increasing the safety relief valve pressure settings may create an explosive bottle hazard. Identify the gas content by the NOS label on the bottle before using. If the bottle is not identified to show the gas contained, return the bottle to the supplier. Do not deface or remove any markings, which are on the nitrous bottle. Nitrous bottle valves should always be closed when the system is not being used. Notify the supplier of any condition, which might have permitted any foreign matter to enter the valve or bottle. Keep the valves closed on all empty bottles to prevent accidental contamination. After storage, open the nitrous bottle valve for an instant to clear the opening of any possible dust or dirt. It is important that all threads on the valves and solenoids are properly mated. Never force connections that do not fit properly. CONGRATULATIONS on purchasing your NOS Nitrous Oxide Injection System. Your system is composed of the highest quality components available. It should provide many miles of trouble-free performance when used correctly. If you have any questions regarding the performance of your system, call NOS Technical Service at 1-714-546-0592, fax to 1-714-545-8319, or email to www.nos@support.holley.com. 2
TABLE OF CONTENTS What is Nitrous Oxide?... 4 Do s and Don ts of Nitrous Oxide.4 Chapter 1 Introduction to Your Progressive Nitrous Controller.4 1.1 General Information. 4 1.2 Operating Principle.. 5 1.3 System Requirements........ 5 1.4 Kit Components 5 Chapter 2 Installation..... 8 2.1 Throttle Position Sensor and Bracket. 8 2.2 Redundant Nitrous Solenoid. 9 2.3 Control Module Mounting.. 9 2.4 System Wiring... 9 2.4.1 System Wiring (Dry Manifold Systems). 9 Chapter 3 Preparing for Operation...... 10 3.1 Throttle Position Sensor Adjustment..10 3.2 Fuel Jetting Modification 11 3.3 System Checkout. 11 Chapter 4 Tuning Suggestions... 11 Chapter 5 Maintenance.. 11 5.1 Solenoid Inspection and Maintenance... 12 Appendix A General Jetting Tips 13 Appendix B Troubleshooting Guide.. 14 LIST OF FIGURES AND TABLES Figure 1 Parts Identification.... 6 Figure 2 Carbureted Exploded View...... 7 Figure 3 Installed TPS Actuator Arm.... 8 Figure 4 Installed TPS Assembly... 8 Figure 5 Color Coding of TPS Plug 9 Figure 6 Wiring Diagram...... 10 Figure 7 Indexing TPS 11 Figure 8 Solenoid Exploded View... 12 Figure 9 Solenoid Exploded View.. 12 Figure 10 Solenoid Seal. 13 Table 1 Parts List.... 5 Table 2 Solenoid Rebuild Kit Part Numbers 12 Table 3 Super Powershot Jetting Map..... 13 Table 4 Cheater Jetting Map. 14 Table 5 Multi-Carburetor Cheater Jetting Map 14 3
WHAT IS NITROUS OXIDE? NITROUS OXIDE Is a cryogenic gas composed of nitrogen and oxygen molecules Is 36% oxygen by weight Is non-flammable by itself Is stored as a compressed liquid Exists in two grades U.S.P. and Nitrous Plus: U.S.P. is medical grade nitrous oxide; its common use is dental and veterinary anesthesia. It is also commonly used as a propellant in canned whipped cream. U.S.P. is not available to the public. Nitrous Plus differs from U.S.P. in that it contains trace amounts of sulphur dioxide added to prevent substance abuse. Nitrous Plus is intended for automotive applications and is available for sale to the public In automotive applications, Nitrous Plus and fuel are injected into the engine s intake manifold, which produces the following results: Lowers engine intake air temperature, producing a dense inlet charge. Increases the oxygen content of the inlet charge (air is only 22 percent oxygen by weight). Increases the rate at which combustion occurs in the engine s cylinders. Do s and Don ts of Nitrous Oxide Do s Don ts Read all instructions before attempting to install your NOS nitrous system. Use a high-pressure fuel injection style fuel pump. Use a by-passing type fuel pressure regulator. Make sure your fuel delivery system is adequate for the nitrous jetting you have chosen. Inadequate fuel pressure or flow will result in engine damage. Use the recommended gauge of wire when installing electrical system components. Use Teflon-based paste on pipe style fittings. Make sure your engine and related components (ignition and driveline) are in proper working condition. Check solenoid plunger seals frequently, as described in the maintenance section. Rewire the existing nitrous system to match the wiring diagram supplied with this kit. If nitrous is accidentally injected into the engine when it is not running, remove the engine coil wire, open the throttle, and crank the engine 10 to 15 seconds before starting. Failure to do so can result in an explosive engine failure. Activate your NOS nitrous system only at engine speeds as outlined in your systems owner s manual. Install a proper engine to chassis ground. Failure to do so may result in an explosive failure of the main nitrous supply line. Engage your nitrous system with the engine off. Severe engine damage can occur. Use octane boosters that contain methanol. Damage to the nitrous and fuel solenoids can occur. Modify NOS nitrous systems (if you need a non-stock item, call NOS Technical Service for assistance). Operate this system with a low-pressure (carbureted style) fuel pump. Inconsistent performance can result. Operate this system with a dead-heading type fuel pressure regulator. Inconsistent performance can result. Overtighten AN type fittings. Use Teflon Tape on any pipe threads. Pieces of Teflon tape can break loose and become lodged in nitrous or fuel solenoids or solenoid filters. Debris lodged in a nitrous or fuel solenoid can cause catastrophic engine failure. Use sealant of any kind on AN type fittings. Allow nitrous pressure to exceed 1100 psi. Excessive pressure can cause swelling or in extreme cases, failure of the nitrous solenoid plunger. Solenoid plungers are designed so that pressure-induced failures will prevent the valve from operating. No leakage should occur with this type of failure. Inhale nitrous oxide. Death due to suffocation can occur. Allow nitrous oxide to come in contact with skin. Severe frostbite can occur. Operate this system without the safety solenoid in place. Explosive engine failure can occur. Attempt to use this system with nitrous kits that inject nitrous and fuel ahead of the throttle plate. Explosive engine failure can occur. Chapter 1 Introduction to your NOS Nitrous Oxide Kit 1.1 General Information Your NOS Progressive Nitrous Oxide Injection Controller is designed to provide you with a much smoother application of power than conventional nitrous oxide injection kits. Kit #15835NOS is intended to work with most standard flange Holley carburetors that have mechanical secondaries. If you wish to utilize this kit n a carburetor other than it was designed for, an alternate TPS bracket must be fabricated. It is designed to operate two primary solenoids, with a maximum amperage draw of 12 amps. 4
By varying the amount of nitrous oxide injected into the engine, proportional to the throttle position, the behavior of the system changes dramatically. No longer do you have the brutal on/off transition characteristic of conventional nitrous oxide injection kits. Your vehicle will now react just as if it had a much larger engine. By controlling horsepower output proportional to the throttle position, you will be able to minimize wheel spin and maximize controllability, thereby achieving the maximum acceleration possible. 1.2 Operating Principle Flow of nitrous oxide into your engine is controlled by a microprocessor, using the technique known as Pulse Width Modulation. This is the same principle employed on all factory fuel injection systems. In simple terms, this means that the solenoids are opened and shut 25 times per second. The length of time that they are held open is linearly proportional to the throttle position (closed at idle, open continuously at wide-open throttle). Conventional jets are used in both the nitrous and fuel sides of your NOS nitrous oxide injection system to limit total power output. A secondary or redundant solenoid is used on the nitrous side of the system as a safety feature. When the throttle begins to open, this secondary solenoid opens 100% and stays open until the throttle is returned to the closed position. Once the throttle closes, this secondary solenoid also closes, preventing accidental leakage of nitrous oxide into the engine. 1.3 System Requirements Fuel System The fuel side of your nitrous oxide injection system needs to be operated at fuel pressures higher than typical carbureted systems. NOS recommends that a fuel pressure of at least 15 psi be maintained. To accomplish this, you will need a high-pressure (fuel injection type) fuel pump and by-passing regulator. Additionally, fuel jetting of carbureted style nitrous systems will need to be changed to accommodate the higher fuel pressure. Appendix A provides detailed jetting combinations for all popular NOS nitrous oxide injection kits. Redundant Solenoid A secondary or redundant solenoid must be used on the nitrous side. The NOS solenoid designed to work in this application is included in this kit. WARNING: Due to the cyclic nature of the solenoid operation, use of this kit will reduce the life expectancy of the primary nitrous solenoid plunger. Do not attempt to operate this system without the redundant nitrous solenoid in place. Doing so can result in leakage of nitrous oxide into the engine and catastrophic engine explosion, resulting in injury or death. 1.4 Kit Components Before beginning the installation of your NOS kit, compare the components in your kit with those illustrated in Figure 1 and listed in Table 1. If any components are missing, please contact NOS Technical Support at 1-714-546-0592. Table 1 Throttle Position Controlled Progressive Controller #15835NOS Parts List Item Description Quantity NOS P/N (1) TPS Arm 1 15862 (2) TPS 1 25637 (3) TPS Mounting Bracket 1 15863 (4) TPS Mounting Screw 2 16423 (5) TPS Mounting Nut 2 17931 (6) 1 ft. 4AN Hose (Blue) 1 15210 (7) Pro Shot Redundant Solenoid 1 16040 (8) N 2O Filter 1 15560 (9) 1/8 NPT 4AN Fitting 1 17960 (10) Solenoid Bracket 1 16500 (11) Solenoid Mounting Screw 2 16501 (12) Control Module 1 15835-S (13) 3/8 Shrink Tube 1 16849-S (14) Male Pin 3 15793 (15) Packard Seal 3 15794 (16) 3-Pin Male Connector 1 15783 (17) 30 AMP Relay 1 15618 (18) Relay Harness 1 15604 (19) Female Spade Connector (Red) 3 15885R (20) Male Spade Connector (Blue) 2 15886B (21) Large Wire Eyelet 1 15883 (22) Small Wire Eyelet 3 15881-S (23) Female Spade Connector (Blue) 1 15885B-S (24) Male Spade Connector (Green) 2 15888G-S (25) Female Spade Connector (Green) 1 15889G-S (26) 25 AMP Fuse 1 15893-25-S 5
Figure 1 Progressive Nitrous System Parts Identification 6
Figure 2 Carbureted Exploded View 7
Figure 3 Installed TPS Actuator Arm Figure 4 Installed TPS Assembly Chapter 2 Installation 2.1 Throttle Position Sensor and Bracket NOTE: Carburetor choke modifications may be necessary in order to install the throttle position sensor and bracket. 1. Remove the air filter assembly. 2. Install the TPS actuator arm (1) on the carburetor secondary throttle shaft, as shown in Figure 3. NOTE: In some instances, a longer accelerator pump cam screw may be required to attach the actuator arm and cam to the secondary throttle shaft. 3. Loosely secure the throttle position sensor (2) onto the throttle position sensor bracket (3) using the screws (4) and nuts (5). 4. Install the throttle position sensor and bracket assembly on the carburetor. See Figure 4. 8
NOTE: In some applications, longer carburetor studs may be required. 2.2 Redundant Nitrous Solenoid 1. Attach the 1 ft. 4AN Hose (6) to the primary nitrous solenoid. 2. Place the redundant nitrous solenoid (7) in a bench vise. 3. Install the nitrous filter (8) in the inlet port of the redundant solenoid. 4. Install the 1/8NPT to 4AN fitting (9) in the outlet port of the redundant solenoid. 5. Remove the solenoid from the vise. Choose the mounting location for the redundant nitrous solenoid. The redundant nitrous solenoid must be located where the 1 ft. 4AN hose will reach the primary nitrous solenoid outlet port. 6. Secure the redundant solenoid with the mounting bracket (10) and the screws (11). 7. Connect the 1 ft. 4AN Hose to the redundant nitrous solenoid outlet port. 2.3 Control Module Mounting 1. Locate a suitable mounting location within the engine compartment or interior of the vehicle for the control module (12). The control module should not be mounted near the spark plug wires, ignition components, or exposed to extreme heat. Secure in place. HINT: Lay out all the wiring leads before securing the control module in place to ensure that the leads reach the components. 2. Trim the TPS cable lead from the control module to the desired length. Leave approximately 2 inches of wire exposed at the open end. 3. Slip a 1 inch piece of shrink tube (13) over the open end of the wire covering. Heat with a hair dryer until the shrink tube is secured. 4. Install the male pins (14), seals (15), and the male 3-pin connector (16) on the open wires, using the color coding shown in Figure 5. HINT: NOS suggests that for maximum durability, the male pins be soldered as well as crimped onto the wire leads. 5. Connect the 3-Pin connector to the throttle position sensor. Figure 5 TPS Color Coding 2.4 System Wiring 2.4.1 System Wiring (Dry Manifold Systems) NOTE: If the nitrous system that this kit is to be used in conjunction with has been previously installed, the original wiring must be removed and replaced. Refer to Figure 6 for a complete wiring diagram of this system. 1. Disconnect the vehicle s battery. 2. Mount the relay (17) and relay harness (18) in a location convenient to an ignition switched +12V power source. 3. Connect terminal #1 of the arming switch to an ignition switched +12V source, using a female spade connector (19). 4. Connect terminal #2 of the arming switch to the red wire on the relay and the red wire from the control module, suing a green male spade connector (24). 5. Connect terminal #3 of the arming switch to a good chassis ground, using a small eyelet (22). 6. Connect the orange relay wire from the relay to the (+) battery terminal, using a large eyelet (21). 7. Connect the green relay wire to the brown wire from the control module, using a green male spade connector (24). 8. Connect one wire from each of the three solenoids to the blue relay wire, using a blue male spade connector (20). NOTE: Solenoids are not polarized, either solenoid lead wire will do. 9. Connect the remaining wire from the redundant solenoid to a good chassis ground, using a small eyelet (22). 9
10. Connect the remaining wires from the primary nitrous and fuel solenoids together using a single male spade connector (20). Connect these two wires to the white wire from the control module, using a blue female spade connector (23). 11. Connect the black wire from the control module to a good chassis ground, using a small eyelet (22). 12. Install the 25 AMP fuse (26) into the fuse socket on the orange relay wire. 13. Connect the battery. Figure 6 Wiring Diagram Chapter 3 Preparing for Operation 3.1 Throttle Position Sensor Adjustment 1. Disconnect the solenoids from the control module. 2. Turn the arming switch and vehicle ignition OFF. 3. Using a digital volt/ohm meter, check the resistance between terminals B and C, with the throttle in the closed position, as shown in Figure 7. Resistance should be approximately 5400 ohms. Adjust the rotational position of the TPS until this resistance is reached. 4. Set the throttle to wide open. Check the resistance between terminals B and C. Resistance should be approximately 2450 ohms. WARNING: Correct indexing of the TPS sensor is critical. If the sensor is incorrectly indexed (advanced), nitrous oxide may be introduced into the engine whenever the system is armed, producing an explosive engine condition. 10
Figure 7 Indexing TPS 5. Tighten the throttle position sensor in place. 6. Connect the solenoids to the control module. 3.2 Fuel Jetting Modification As mentioned in Section 1.0 General Information, the use of this system requires fuel pressure higher than those typically used in carbureted engines. Once a fuel pressure level has been decided upon and set, replace the fuel jet(s) in your system with jet(s) corresponding to your new fuel pressure. HINT: The tables in Appendix A have been provided to aid you in jet selection for all popular NOS nitrous oxide injection systems. Before selecting a fuel pressure, it is wise to examine these tables for suggested jetting combinations. Try to choose a fuel pressure level that allows the fuel jet(s) to be at least #16 - #18 (the smaller the fuel jet size, the more critical the filtering capability of your fuel filter). 3.3 System Checkout CAUTION: Before performing the following steps, ensure that the nitrous bottle valve is off and the nitrous feed line is empty. Failure to do so can result in an intake manifold explosion, causing serious injury or death. 1. Close the nitrous bottle valve if it is open. Purge the nitrous from the supply line. 2. Turn the vehicle ignition to ON. Turn the arming switch to ON. NOTE: If the vehicle employs an electrical fuel pump, the pump should be shut off for Step 3. 3. Manually operate the throttle linkage. Fuel and primary nitrous solenoids should both make a clicking noise, the frequency of which changes with the throttle position sensor movement. When the throttle is in the closed (idle) position, the solenoid should be silent. If not, check the TPS sensor indexing. 4. Start the engine. 5. Set the engine speed at approximately 2000 RPM. Slowly operate the throttle position sensor manually. Engine speed should decrease if the system is performing properly. 6. Set the engine speed at idle. Open the nitrous bottle valve. There should be no change in engine speed. 7. Check the nitrous lines and fittings for leaks. 8. ENJOY! Chapter 4 Tuning Suggestions Appendix A provides jetting recommendations for popular NOS nitrous oxide injection kits. If your system is not shown, call the NOS technical department at 714-546-0592 for tuning suggestions. Chapter 5 Routine Maintenance The cyclic operating nature of this system greatly reduces the life expectancy of the primary nitrous solenoid plunger. A worn or damaged plunger can cause leakage or improper metering of nitrous; the result of which may be engine damage or fire. For these reasons, it is important to routinely inspect the primary nitrous solenoid plunger seal every 6 minutes of operation (6 minutes of activated time). Follow the procedures listed below for solenoid inspection and maintenance. For additional solenoid information, see NOS Technical Bulletin #201. 11
5.1 Solenoid Inspection and Maintenance 1. Turn off the nitrous bottle valve. 2. Carefully relieve the pressure in the nitrous lines. CAUTION: Inhalation of nitrous oxide can cause death. Contact of skin with nitrous oxide can cause severe frostbite. 3. Unscrew the retaining nut from the top of the solenoid. See Figures 8 and 9 for the solenoid exploded views. 4. Remove the solenoid coil. 5. Place the spanner nut over the solenoid stem and engage the drive dowels in the holes in the top of the stem. Remove the stem turning the spanner nut counterclockwise. NOTE: Do not grip the stem. Damage to the stem will result. 6. Remove the plunger and the spring. Examine the seat for damage. Figure 10 shows a plunger in good working condition. If there are any cuts or evidence of missing plunger material, discard the plunger, spring, and base seal. Replace the components with new NOS service parts. Table 2 lists the solenoid rebuild kits for all popular NOS solenoids. 7. Repeat steps 3-6 in the reverse order. Table 2 Solenoid Rebuild Kit Part Numbers Solenoid Number Requires Kit Number: 16000 16001 16020 16021 16025 16026 16030 16021 16032 16021 16040 16041 16045 16046 16050 16051 16080 16081 12
Figure 8 Powershot Exploded View Figure 9 Cheater Exploded View Figure 10 Solenoid Seal Normal wear should be flat except for small circular indentation. Appendix A General Jetting Tips In most applications, maintaining a nitrous/fuel ratio between 5.0:1 (richer) and 6.0:1 (leaner) will provide optimum performance. When changing the jetting, it is suggested that you start with a rich (5.0:1) nitrous/fuel ratio. Lean the nitrous/fuel jetting until the desired performance is achieved. CAUTION: Be careful not to run an excessively high nitrous/fuel ratio. Severe engine damage can occur. Jetting combinations for fuel pressures from 10 to 90 psi are listed in this appendix for all popular NOS nitrous oxide injection kits. For a particular nitrous jet/fuel pressure combination, the larger fuel jet listed, will produce a 5.0:1 nitrous/fuel ratio. The smaller fuel jet should yield a ratio of about 6.0:1. 13
NOTE: These nitrous/fuel ratios are attained with the nitrous bottle pressure between 900 and 925 psi. Higher pressures will result in leaner nitrous/fuel ratios. Lower pressures will yield a richer mixture. Table 3 Super Powershot Jetting Map Nitrous Jet Suggested Fuel Jet @ PSI 900-925 PSI 4 6 8 10 20 30 40 50 60 70 80 90 47 51-55 44-49 40-45 37-41 33-36 32-34 N/A N/A N/A N/A N/A N/A 55 53-61 49-53 45-51 41-47 36-38 34-36 32-34 N/A N/A N/A N/A N/A 73 70-82 51-60 47-53 45-51 37-40 36-38 33-36 33-35 32-34 N/A N/A N/A Jetting combinations are for engines with single stage nitrous systems only. NOTE: Always start tuning a nitrous/fuel ratio richer than you expect to run. Gradually lean out the mixture until the desired performance is attained. A slightly rich nitrous/fuel ratio will provide a dramatic increase in engine safety, while only slightly reducing performance. Table 4 Cheater Series Jetting Map Nitrous Jet Suggested Fuel Jet @ PSI 900-925 PSI 4 6 8 10 20 30 40 50 60 70 80 90 73 70-93 60-67 53-60 51-57 41-46 39-44 37-40 35-39 34-37 33-35 32-35 32-44 82 90-102 65-80 59-67 54-61 45-51 42-46 39-45 39-45 36-40 35-37 34-38 33-36 93 93-104 69-82 60-70 55-64 46-52 43-48 40-45 40-45 38-40 36-39 35-39 34-37 102 98-78-98 65-80 62-71 49-53 45-51 43-47 43-47 39-44 38-40 36-40 35-39 Jetting combinations are for engines with single stage nitrous systems only. NOTE: Always start tuning a nitrous/fuel ratio richer than you expect to run. Gradually lean out the mixture until the desired performance is attained. A slightly rich nitrous/fuel ratio will provide a dramatic increase in engine safety, while only slightly reducing performance. Table 5 Multi-Carburetor Cheater Series Jetting Map Nitrous Jet Suggested Fuel Jet @ PSI 900-925 PSI 4 6 8 10 20 30 40 50 60 70 80 90 52 49-65 42-47 37-42 36-40 28-32 27-31 26-28 25-27 24-26 23-25 22-25 22-24 59 63-72 45-56 41-47 38-43 31-36 29-32 27-31 27-31 25-28 25-26 24-26 23-25 65 65-73 48-57 42-49 39-45 32-37 30-34 28-31 28-31 26-28 25-27 25-27 24-26 73 69-55-69 45-56 44-50 34-37 31-36 30-33 30-33 27-31 26-28 25-28 25-27 Jetting combinations are for engines with single stage nitrous systems only. NOTE: Always start tuning a nitrous/fuel ratio richer than you expect to run. Gradually lean out the mixture until the desired performance is attained. A slightly rich nitrous/fuel ratio will provide a dramatic increase in engine safety, while only slightly reducing performance. Appendix B Troubleshooting Guide The troubleshooting chart on the following pages should help determine and rectify most problems with your installed NOS system. If you still need assistance determining or fixing problems, call the NOS Technical Support at 1-714-546-0592. PROBLEM POSSIBLE CAUSES DIAGNOSTIC PROCEDURE CORRECTIVE ACTION No change in performance when system is activated. Malfunctioning TPS. Refer to Chapter 3, Section 3.1 throttle position adjustment. Replace TPS. Malfunctioning control module. Check 12V supply and ground connection. Check connections to solenoids. Check voltage from TPS. Replace control module or repair faulty connections. System runs rich when activated. A5073-SNOS Date: 08-16-01 Malfunctioning safety solenoid. Malfunctioning control module. Disconnect primary nitrous and fuel solenoid wires. Arm and activate the nitrous system. A loud click should be heard from the safety solenoid. Disconnect primary nitrous and fuel solenoid wires. Arm and activate nitrous system. Check for 12V at safety solenoid wire. NOS Technical Support 1357 E. Grand Ave. Pomona, CA 91766 Phone: 714-546-0592 Fax: 714-545-8319 Email: nos@support.holley.com Replace the safety solenoid. Replace control module. 14