How does a secondary air injection system work?
Secondary Air Injection is an emission control that uses an air pump (either electric or turned by the drive belt) to move fresh air into the exhaust manifold (s) or exhaust ports when the engine is in open loop and pre-catalytic converter when in closed loop. This reduces hydrocarbon emissions (HC), Carbon Monoxide (CO),…
What are the components of an air injection pump?
The air injection system introduces oxygen into the exhaust engine at certain times to reduce emissions. Typical system components include the PCM, air injection relay, air injection hoses, valves and the pump. The air injection pump can be either belt driven or electric – for this article, we will focus on the belt-driven design.
Where is the air injection pump located on a car?
Typically, the Check Engine Light will be illuminated and diagnostic trouble codes (DTCs) will be stored in the PCM. Step 1: Locate the air injection pump. The air pump is at the front of the engine with the serpentine belt wrapped around it.
How does the air injection system self check?
To self-check, the AIR system will be activated by the PCM and fresh air would be routed into the exhaust system. The oxygen sensors would sense this fresh air as a lean condition and the short term fuel trims would begin to move in the positive direction to compensate.
How to replace a secondary air injection pump?
Step 1: Locate the air injection pump. The air pump is at the front of the engine with the serpentine belt wrapped around it. Tip: Make sure there is a belt routing diagram under the hood of your car so you know how to reinstall the belt. If not, take a picture of the belt routing with your phone before proceeding further.
The air injection system introduces oxygen into the exhaust engine at certain times to reduce emissions. Typical system components include the PCM, air injection relay, air injection hoses, valves and the pump. The air injection pump can be either belt driven or electric – for this article, we will focus on the belt-driven design.
Typically, the Check Engine Light will be illuminated and diagnostic trouble codes (DTCs) will be stored in the PCM. Step 1: Locate the air injection pump. The air pump is at the front of the engine with the serpentine belt wrapped around it.
What happens when an air injection pump goes bad?
Problems with the air injection system can result in increased emissions and engine performance issues. Typically, the Check Engine Light will be illuminated and diagnostic trouble codes (DTCs) will be stored in the PCM. Step 1: Locate the air injection pump.
This component is also called a smog pump, or an air pump, and it lies within the secondary air injection system of the vehicle. It can reduce carbon emissions by pumping fresh air from outside into the exhaust stream. By the time fumes leave the tailpipe, there are fewer hydrocarbon pollutants in them.
How to test the secondary air system component?
You can test the function of the secondary air components using a Mercedes-Benz scan tool. If you do not have access to one, you can check secondary air pump function when starting the engine.
When to replace a secondary air injection pump?
If you’ve already experienced engine stalling, poor acceleration, and a check engine warning light, then you need to have the secondary air injection pump checked out immediately. If it is proven to be the problem, have it replaced by a certified mechanic.
Can a solid state unit be tested with secondary current injection?
Secondary current injection. Solid-state trip units can be tested via secondary current injection using a test set specifically designed for the device to be tested. The main shortcoming of the secondary current injection test method is that only the solid-state trip unit logic and components are tested.
How can I Check my secondary air injection pump?
Inspect the combination valve. You have to use a vacuum pump to inspect whether the combination valve is running properly or not. To do this, you have to detach the valve’s vacuum line and connect the pump to the valve. A hose fitting connects the combination valve to the secondary air ignition pump.
This component is also called a smog pump, or an air pump, and it lies within the secondary air injection system of the vehicle. It can reduce carbon emissions by pumping fresh air from outside into the exhaust stream. By the time fumes leave the tailpipe, there are fewer hydrocarbon pollutants in them.
You can test the function of the secondary air components using a Mercedes-Benz scan tool. If you do not have access to one, you can check secondary air pump function when starting the engine.
Secondary current injection. Solid-state trip units can be tested via secondary current injection using a test set specifically designed for the device to be tested. The main shortcoming of the secondary current injection test method is that only the solid-state trip unit logic and components are tested.
If you’ve already experienced engine stalling, poor acceleration, and a check engine warning light, then you need to have the secondary air injection pump checked out immediately. If it is proven to be the problem, have it replaced by a certified mechanic.
What are the symptoms of an air injection pump failure?
Below you’ll find the five most common symptoms of secondary air injection pump failure. If you notice at least two of the symptoms occurring, there’s a good chance you’re dealing with a faulty secondary air injection pump and you need to get it serviced right away.
How long does the secondary air pump run?
The secondary air pump only runs for 2 minutes just after starting a cold engine. Even less if the engine warms up quickly on a warm day. It pumps air into the exhaust stream when the engine is running rich.
What are the methods of pumped air injection?
Methods of implementation. Pumped air injection. Pumped air injection systems use a vane pump called the air pump, AIR pump, or colloquially “smog pump” turned by the engine via a belt or electric motor.
Why do you need a secondary air pump?
Another noteworthy purpose of the secondary air pump is to prevent damage to the exhaust system by blowing out any accumulated water vapor that could freeze the system. This function is necessary when the system detects the ambient air is below -10 degrees C (-14 degrees F).
Methods of implementation. Pumped air injection. Pumped air injection systems use a vane pump called the air pump, AIR pump, or colloquially “smog pump” turned by the engine via a belt or electric motor.
Another noteworthy purpose of the secondary air pump is to prevent damage to the exhaust system by blowing out any accumulated water vapor that could freeze the system. This function is necessary when the system detects the ambient air is below -10 degrees C (-14 degrees F).
What are the symptoms of a bad air injection pump?
One of the early symptoms of a bad secondary air injection pump is the Check Engine warning light turning on. The engine control unit can automatically detect when the secondary air injection pump has a problem.
Why do we need an air injection system?
All we have to do is introduce some oxygen, than any unburned fuel will ignite. So, the air injection smog pump pushes air into the exhaust system, right after the exhaust manifold. Therefore, helping intercept and burn those unburned fuels. Above all, the system is critical to help engines achieve government emissions standards.
When to remove and plug the pulse air injection system?
Removal & plugging of the Pulse Air system is quite commonly done. This will also usually eliminate any tendency for back-snapping in the exhaust during trailing throttle (if the PulseAir System was causing it). Will I have to change jetting or settings of the carburetors or ignition?
Where does the air come from for air injection?
A sensitive reed valve assembly called the aspirator valve is placed in the air injection pumping, which draws its air directly from the clean side of the air filter. During engine idle, brief but periodic negative pressure pulses in the exhaust system draw air through the aspirator valve and into the exhaust stream at the catalytic converter.
A sensitive reed valve assembly called the aspirator valve is placed in the air injection pumping, which draws its air directly from the clean side of the air filter. During engine idle, brief but periodic negative pressure pulses in the exhaust system draw air through the aspirator valve and into the exhaust stream at the catalytic converter.
What do you need to know about a secondary air pump?
If you’re wondering what a secondary air injection pump is, you’re not alone. In this article, we’ll go over the purpose of the secondary are pump as well as the symptoms you should watch for that indicate the pump is failing. What Does a Secondary Air Pump Do? What Does a Secondary Air Pump Do?
To reduce loads on the electrical system, the PCM feeds power to the SAI pump via a relay (relay “A” in this case) that delivers battery voltage through a fuse or fusible link to the SAI pump motor. The image below shows a simplified schematic drawing of a typical secondary air injection system.
How does the secondary air pump and relay work?
Filtered air is drawn from the engine air cleaner assembly. The powertrain control module (PCM) monitors the Secondary air injection (AIR) System for faults during cold start-up operation. When the system’s pressure or relay circuits operations vary too far from the predicted values, a DTC will set.
When to replace a Sai air pump relay?
Replace the relay with an OEM replacement if any tested value does not agree with the values stated in the manual. If relay “A” checks out, prepare to perform resistance, continuity, and ground integrity checks on all associated wiring, but be sure to disconnect the SAI wiring from the PCM to prevent damaging the controller during resistance tests.
When do you need a secondary air injection system?
Whenever there are loose ends, leaks, or any other kind of illogical airflow, the engine is wasting power.
Why is the DTC p0418 relay’a’circuit not working?
The DTC P0418 is detected the the AIR vacuum control solenoid circuit not operating as desired by the PCM. An air pump is used on the vehicle to lower tail pipe emissions on start-up. The Powertrain Control Module ( PCM) grounds the Air pump relay control circuit which energizes the Air pump.
How does the air combination valve solenoid circuit work?
The PCM also grounds the Air combination valve vacuum control solenoid circuit, which energizes the Air vacuum control solenoid. Vacuum is then applied to both Air combination valve diaphragms which opens the shut off valves. The PCM enables both circuits simultaneously when Air system operations id desired.
Secondary air injection systems pump outside air into the exhaust stream so unburned fuel can be burned. Newer aspirated systems use the vacuum created by an exhaust pulse to pull air into the pipe. The latest systems use an electric motor to pump air. These systems are critical for the life of the catalytic converter.
How does secondary air injection system work?
What does a secondary air injection system do?
Secondary air injection (commonly known as air injection) is a vehicle emissions control strategy introduced in 1966, wherein fresh air is injected into the exhaust stream to allow for a fuller secondary combustion of exhaust gases. 1 Development. Oct 12 2019
Do you need a secondary air injection system?
The air injection smog pump pushes air into the exhaust system right after the exhaust manifold, to help intercept and burn those unburned fuels. The system is critical to help cars achieve government emissions standards. So, the law says you need a secondary air injection system .
What is the purpose of secondary air injection?
The primary purpose of a secondary air injection system is to consume the excess fuel that is injected during cold-start enrichment before it can reach the catalytic converter. This has the effect of improving tailpipe emissions.
Where is the secondary air injection system located?
The secondary air injection pump is located under the left corner of the front bumper area.The pump is accessed from under the vehicle with the plastic air dam shield removed.