Difference between revisions of "NG 900/9-3 Throttle Body"
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==Overview== | ==Overview== | ||
| − | The throttle body controls the flow of air into the intake. While driving, air flow is controlled by the throttle plate. At idle, through the electrically controlled IAC valve. The throttle body also has inlets for hoses from the evap. emission system purge valve, from the crankcase ventilation system (PCV), and vacuum lines leading the the manifold air pressure sensor (MAP), the fuel pressure regulator (FPR), and the turbo bypass valve (BPV). Note: hose connections for the non-turbo version of the engine, and later 9-3 models are different. | + | The throttle body controls the flow of air into the intake. While driving, air flow is controlled by the throttle plate. At idle, through the electrically controlled IAC valve. The throttle body also has inlets for hoses from the evap. emission system purge valve, from the crankcase ventilation system (PCV), and vacuum lines leading the the manifold air pressure sensor (MAP), the fuel pressure regulator (FPR), and the turbo bypass valve (BPV). Note: hose connections for the non-turbo version of the engine, and later 9-3 models are different. Figs. 1 and 2 |
| + | [[File:90093_TB_1.jpg|thumb|Fig. 1 - Throttle Body Overview]] | ||
| + | [[File:90093_TB_4.jpg|thumb|Fig. 2 - Throttle Body]] | ||
===Idle Air Control Valve=== | ===Idle Air Control Valve=== | ||
| − | The IAC valve is a solenoid controlled valve which regulates the flow of air into the engine during idle. It may require cleaning every few years, and more often on engines where the crankcase ventilation system or the turbo leak an excessive amount of oil into the intake. For details see [http://pages.infinit.net/mlbriand/saab/iac/page1.html| Michel Briand's Cleaning Directions]. | + | The IAC valve is a solenoid controlled valve which regulates the flow of air into the engine during idle. It may require cleaning every few years, and more often on engines where the crankcase ventilation system or the turbo leak an excessive amount of oil into the intake. For details see [http://pages.infinit.net/mlbriand/saab/iac/page1.html| Michel Briand's Cleaning Directions]. Fig. 3 |
| + | [[File:90093_TB_3.jpg|thumb|Fig. 3 - Idle Air control Valve]] | ||
===Engine Coolant Connections=== | ===Engine Coolant Connections=== | ||
| − | Engine coolant circulates through a section of the throttle body by way of two hoses connected to the engine, to help prevent freeze up during winter. | + | Engine coolant circulates through a section of the throttle body by way of two hoses connected to the engine, to help prevent freeze up during winter. Fig. 4 |
| + | [[File:90093_TB_2.jpg|thumb|Fig. 4 - Coolant Connections]] | ||
===Cleaning and Lubrication=== | ===Cleaning and Lubrication=== | ||
| − | The inside of the throttle body may need cleaning every few years around the throttle plate. The throttle arm springs and bushing can stick and may require lubrication, and the throttle position sensor (TPS) can wear out. The tar around the circumference of the throttle plate is from the same source as the IAC valve contamination. | + | The inside of the throttle body may need cleaning every few years around the throttle plate. The throttle arm springs and bushing can stick and may require lubrication, and the throttle position sensor (TPS) can wear out. The tar around the circumference of the throttle plate is from the same source as the IAC valve contamination. Fig. 5 |
| + | [[File:90093_TB_6.jpg|thumb|Fig. 5 - Throttle Body Cleaning]] | ||
===Throttle Position Sensor=== | ===Throttle Position Sensor=== | ||
| − | The TPS is a rotary potentiometer which indicates the position of the throttle plate. With the connector unplugged, the resistance measured between pins 1 and 3 should change gradually between 2.5k Ohms with throttle plate closed, and 1.0k Ohms fully open. | + | The TPS is a rotary potentiometer which indicates the position of the throttle plate. With the connector unplugged, the resistance measured between pins 1 and 3 should change gradually between 2.5k Ohms with throttle plate closed, and 1.0k Ohms fully open. Fig. 6 |
| + | [[File:90093_TB_8.jpg|thumb|Fig. 6 - Throttle Body]] | ||
===Throttle Body Connections=== | ===Throttle Body Connections=== | ||
| − | Numbers correspond with labels in Fig. | + | Numbers correspond with labels in Fig. 7 |
1 - Crankshaft ventilation hose (PCV) | 1 - Crankshaft ventilation hose (PCV) | ||
2 - Air Pressure sensor (MAP) | 2 - Air Pressure sensor (MAP) | ||
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4 - Turbo bypass valve (BPV) | 4 - Turbo bypass valve (BPV) | ||
5 - Evap emission system purge valve | 5 - Evap emission system purge valve | ||
| − | 6 | + | 6 and 7 - IAC valve hoses |
| − | 8 | + | 8 and 9 - Coolant hoses |
| + | |||
| + | [[NG900/9-3_Vacuum_Lines| Vacuum and PCV Lines]] | ||
| + | [[File:90093_TB_5.jpg|thumb|Fig. 7 - Throttle Body Connections]] | ||
===Bottom View=== | ===Bottom View=== | ||
| − | The vacuum lines are connected into two chambers at the bottom of the throttle body, which open into the intake manifold. Also note groove for the gasket between the throttle body and the manifold. | + | The vacuum lines are connected into two chambers at the bottom of the throttle body, which open into the intake manifold. Also note groove for the gasket between the throttle body and the manifold. Fig. 8 |
| + | [[File:90093_TB_7.jpg|thumb|Fig. 8 - Throttle Body Bottom View]] | ||
==Part Numbers== | ==Part Numbers== | ||
Revision as of 10:20, 4 November 2009
Contents
Overview
The throttle body controls the flow of air into the intake. While driving, air flow is controlled by the throttle plate. At idle, through the electrically controlled IAC valve. The throttle body also has inlets for hoses from the evap. emission system purge valve, from the crankcase ventilation system (PCV), and vacuum lines leading the the manifold air pressure sensor (MAP), the fuel pressure regulator (FPR), and the turbo bypass valve (BPV). Note: hose connections for the non-turbo version of the engine, and later 9-3 models are different. Figs. 1 and 2
Idle Air Control Valve
The IAC valve is a solenoid controlled valve which regulates the flow of air into the engine during idle. It may require cleaning every few years, and more often on engines where the crankcase ventilation system or the turbo leak an excessive amount of oil into the intake. For details see Michel Briand's Cleaning Directions. Fig. 3
Engine Coolant Connections
Engine coolant circulates through a section of the throttle body by way of two hoses connected to the engine, to help prevent freeze up during winter. Fig. 4
Cleaning and Lubrication
The inside of the throttle body may need cleaning every few years around the throttle plate. The throttle arm springs and bushing can stick and may require lubrication, and the throttle position sensor (TPS) can wear out. The tar around the circumference of the throttle plate is from the same source as the IAC valve contamination. Fig. 5
Throttle Position Sensor
The TPS is a rotary potentiometer which indicates the position of the throttle plate. With the connector unplugged, the resistance measured between pins 1 and 3 should change gradually between 2.5k Ohms with throttle plate closed, and 1.0k Ohms fully open. Fig. 6
Throttle Body Connections
Numbers correspond with labels in Fig. 7 1 - Crankshaft ventilation hose (PCV) 2 - Air Pressure sensor (MAP) 3 - Fuel pressure regulator (FPR) 4 - Turbo bypass valve (BPV) 5 - Evap emission system purge valve 6 and 7 - IAC valve hoses 8 and 9 - Coolant hoses
Bottom View
The vacuum lines are connected into two chambers at the bottom of the throttle body, which open into the intake manifold. Also note groove for the gasket between the throttle body and the manifold. Fig. 8
Part Numbers
- Idle Air Control Valve: 9127200 (SE Turbo, IAC valves on non-turbo, "S" models are different)
- Throttle Position Sensor:
- 8857195 ('94-'95)
- 4661062 ('96), 9181538
- ('97-'98)
- Intake Air Temp Sensor: 9174442
- Coolant Temp Snsr: 9182270, (side of the engine)
- Manifold Temp Snsr: 9177213, (under the fuel rail)
