Last Updated on July 12, 2022 by Domingo E. O’Reilly
If you are new to cars, you could wonder what the intake manifold valve does and how it achieves its chores. The system enhances the engine airflow process, thus improving efficiency and performance. Different car manufacturers have designed the valve differently, but the basic functionality involves closing and opening the valves within the manifold.
Amazingly, cars come with gadgets designed to enhance performance and fuel economy. One of the vital gadgets is the intake manifold runner control system or a variable-length intake manifold. The intake manifold runner valve is a timely innovation that ensures optimal performance of your car.
The intake manifold valve relies on the engine’s computer to execute its functions. The data collected from numerous sensors dictate how the valve opens and closes. If the valve has to work correctly, it should respond and operate in real-time.
How Does the Intake Manifold Runner Control Valve Work?
Before delving into how the valve works, we could better familiarize ourselves with how air accesses the car engine.
First, the air gets pulled through the filter before traveling via the intake tube and the throttle body to the intake manifold.
The manifold has individual runners that supply air to cylinder head ports. The cylinder heads’ valves open to allow air into the combustion chamber, where it is burned after mixing with the fuel.
The primary chore of the intake manifold runner valve is to improve the engine airflow process and ensure optimal engine performance. The valve achieves this chore by diverting airflow and altering the length of the runners.
Altering the length of the runners allows the fine-tuning of the engine’s performance. A longer yet narrow runner permits added power in a low revolution per minute (RPM) range by offering extra torque and improved fuel economy.
On the other hand, a shorter but wide runner offers added high-end power by forcing airflow to endure a tumbling effect, thus providing extra horsepower at high speeds.
Different Designs of Intake Manifold Valves
Intake manifold valves come in many designs. However, most systems feature flaps (butterfly valves) inside the manifold. These flaps help to vary the runners’ length and are controlled by a vacuum-operated actuator or an electric actuator.
Suppose your vehicle uses a vacuum source, then vacuum is supplied to the actuator through a solenoid.
In most cases, the valves restrict access to two pathways for airflow: Short and long pathways. However, some vehicles use a different approach, including blocking off part of a single passage.
What Operates the Flap Actuator?
All system designs employ a computer (Powertrain Control Module, or PMC) to operate the flap actuator. Most systems primarily use a switch or a sensor to deliver the PMC feedback regarding the actuator’s position.
Vehicles also have other engine management sensors, such as the throttle positions sensor, that relays the data to the PMC regarding the car’s operating conditions. Therefore, the sensors’ data enables the PMC to make accurate and informed decisions regarding system operation.
Note: Different Automakers have given their intake manifold runner control (IMRC) valves various names. For instance, the Ford Motor Company calls it an intake manifold runner control valve, while Chrysler calls their component an intake manifold tuning valve.
Symptoms of a Faulty Intake Manifold Runner Valve
A faulty intake manifold runner control system causes a slew of problems to your car. Discussed below are some of the most common indicators of a malfunctioning valve:
Poor Engine Performance
The primary indicator of a faulty intake manifold control valve is poor engine performance coupled with compromised engine speed. The engine doesn’t perform well as it may hesitate under load or run rough.
Suppose you are driving, your engine might suddenly lose power, especially when going uphill or under load. If you experience this unpleasant situation, know that the manifold’s valve is stuck or doesn’t open at all.
Compromised Fuel Economy
A bad IMRC valve might include vacuum leaks that will hinder the engine’s cylinders from supplying the required amount of air when under varying demands, thus poor fuel efficiency.
A minor airflow difference can lead to power loss, thus non-optimal MPG (Miles per Gallon). You can note an increase in fuel usage after modifying your engine by chip tuning, exhaust work, or intake due to a slight airflow difference.
Engine Light (“Check Engine Light”)
If you have a bad intake manifold runner control valve, you will witness the “check engine light” on your dashboard. Other symptoms such as loss of engine power and rough idle depend on how severely the component has malfunctioned.
Please note that a different problem might cause the fault; therefore, ensure that your engine is inspected for vacuum leak by an expert.
Fixing a Faulty Intake Manifold Runner Control Valve
It becomes challenging for DIY nerds to fix a faulty valve since the issue is complex. The causes of a defective intake manifold runner control system can be a faulty sensor, a malfunctioning actuator, and many more.
The technology involved is complex; hence the fixing part should be left to experts who will diagnose and repair appropriately.
The Cost of Replacing an Intake Manifold Valve
The cost of replacing an intake manifold valve depends on the model year and the type of the vehicle. Older cars’ manifold valves are expensive to replace compared to newer models. Generally, the average cost of replacing the valve ranges between $300 and $1,000.
Discussed below is a crucial breakdown of the average intake manifold replacement cost:
The cost of replacing an Intake Manifold Valve of a Luxury Car
The manifold valves of the latest luxury cars featuring an overhead cam engine are pricey. A replacement of such a valve will set you back an average of $800 to $1,000 per valve, whereas a set of 4 valves might cost around $3,000
The Cost of Replacing an Intake Manifold Valve of a Domestic Car
Replacing a manifold valve in a domestic car might be cheaper or expensive, depending on the engine size and the model year. If your domestic vehicle is of a newer model and features an overhead cam, it will set you back around $300 to replace its manifold valve.
What are the Benefits of Replacing an Intake Manifold Valve?
Replacing an intake manifold valve of your car is beneficial in many ways. A simple gesture of changing the valve extends the car’s lifespan and helps in maintaining its performance. Additionally, intake manifold valves enable high-performing engines to function optimally. The valve also allows the engine to achieve a low-speed torque and a higher revolution per minute (RPM) power.
Manifold valves are an essential cog in your vehicle’s engine; thus, it is advisable to change them when the situation demands. Leave the issue unresolved may escalate and cause extra damage, rendering the car irreparable.
Frequently Asked Questions about Intake Manifold Valves
Can I Drive a Car with a Faulty Intake Manifold Valve?
You may opt to drive a car with a faulty intake manifold valve, but the idea is frowned upon by automotive enthusiasts. Driving with a defective valve might result in a misfire that makes driving an unpleasant experience.
What is the Relationship between a Variable Intake Manifold and a Turbocharger?
Technological development has enabled a variable intake manifold to incorporate single and twin-turbocharged engines to provide exceptional results. The variable intake manifold works with the turbocharger to force extra air into the engine to increase the power further.
The Bottom Line
The efficiency of your car’s runner intake manifold runners control valve determines how it performs. Horsepower and torque rely on how the valve opens and closes to divert the airflow. Therefore, for your road beast to function optimally, ensure that the valve is in its best condition.