2018 Mitsubishi Mirage Has A Vacuum Leak

Diagnosing Vacuum Leaks in Your 2018 Mitsubishi Mirage and Effective Repair Strategies

Find Repair Location
Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
40% chance it's the
Leaking Vacuum Hoses
0%
30% chance it's the
Leaking Gaskets and Seals
0%
20% chance it's the
Bad Actuators and Valves
0%
10% chance it's
Something else
The most common reasons a 2018 Mitsubishi Mirage has a vacuum leak are leaking vacuum hoses, leaking gaskets and seals, or bad actuators and valves.
  • Leaking Vacuum Hoses: A cracked or disconnected vacuum hose can lead to a loss of engine vacuum, resulting in poor engine performance and increased fuel consumption.
  • Leaking Gaskets and Seals: Aged or damaged gaskets and seals can lead to fluid leaks, resulting in loss of engine oil or coolant and potential engine damage.
  • Bad Actuators and Valves: A malfunctioning actuator or valve can disrupt the proper operation of the vehicle's systems, leading to issues such as poor engine performance or erratic behavior of components like the HVAC system.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2018 Mitsubishi Mirage has a vacuum leak?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

Problems with the intake manifold gasket can create the following symptoms:

  • Illuminated check engine light
  • Erratic engine performance
  • Oil and coolant leaks
  • Poor gas mileage
  • Stalling

» LEARN MORE: Intake manifold gasket symptoms

Rough idling, lack of power, engine oil leaks, engine burning oil, and illumination of the check engine light are all possible if the PCV valve has clogged. If the check engine light comes on, the on-board diagnostics (OBD) trouble codes will most likely relate to manifold vacuum, air and fuel mixture, PCV system, mass airflow sensor readings, and exhaust and emissions readings. These are all affected in the event the PCV valve is clogged, is stuck fully open, or is stuck fully closed, however, if the valve is stuck fully open, the engine oil seals are not in danger of overpressure.

A bad valve cover gasket will result in an oil leak. You may notice oil under the car or on other parts under the hood. You might also notice a burning smell while driving.

» LEARN MORE: Signs of a bad valve cover gasket

Any time there is an emissions fault the check engine light will be displayed. The purpose of the check engine light is to inform the driver that an emission related fault has been found, and that there are on-board diagnostic (OBD) trouble codes stored in the powertrain or engine control module. Additionally, since the emissions systems are so intertwined into engine control and transmission control systems, symptoms may include nearly any sort of drivability concerns. This may include harsh shifting, failure to shift, hesitation on acceleration, jerking, engine failure to start or run, loss of power, or any number of other drivability issues.

What are the steps to diagnose a vacuum leak in a 2018 Mitsubishi Mirage?

To effectively diagnose a vacuum leak in a 2018 Mitsubishi Mirage, start with a thorough visual inspection of the vacuum hoses and connections. Look for any signs of wear, such as cracks or loose fittings, which can often be the source of leaks. Next, listen for any hissing sounds while the engine is running, as these can indicate escaping air. If you suspect a leak, using a vacuum gauge can provide a more precise assessment; connect it to the intake manifold and check for abnormal readings that suggest a leak. Another practical method is to spray soapy water on the hoses and connections; if bubbles form, you’ve identified the leak. For a more advanced approach, consider performing a smoke test, which involves introducing smoke into the vacuum system to visually locate the leak. Lastly, don’t forget to check for any trouble codes using an OBD-II scanner, as these can provide additional insights into potential vacuum-related issues. By following this structured diagnostic approach, you can efficiently identify and address vacuum leaks in your vehicle.

What are the common causes and symptoms of a vacuum leak in a 2018 Mitsubishi Mirage?

When diagnosing a vacuum leak in your 2018 Mitsubishi Mirage, it's essential to understand the common problems that can arise. One of the primary culprits is worn-out hoses, which can crack or develop holes over time, allowing air to escape and disrupting the engine's performance. Additionally, a faulty intake manifold gasket can lead to significant leaks, as can loose connections between vacuum hoses and fittings. It's also important to inspect the vacuum lines for any punctures or tears, as these can compromise the system's integrity. A malfunctioning vacuum pump may further exacerbate the issue, leading to a range of symptoms. Drivers often notice a rough idle, indicating that the engine is struggling to maintain a steady RPM. You might also experience decreased performance, characterized by reduced power and acceleration, which can be frustrating during daily driving. The check engine light may illuminate on your dashboard, serving as a warning that something is amiss. In some cases, a hissing noise can be heard under the hood, signaling a leak, while hard starting or prolonged cranking can indicate that the engine is not receiving the proper air-fuel mixture. By being aware of these common causes and symptoms, you can take proactive steps to identify and resolve vacuum leaks, ensuring your Mitsubishi Mirage runs smoothly and efficiently.

How urgent is it to address the vacuum leak in my 2018 Mitsubishi Mirage?

Addressing a vacuum leak in your 2018 Mitsubishi Mirage is not just a matter of routine maintenance; it is an urgent issue that requires immediate attention. A vacuum leak can severely compromise engine performance, leading to symptoms such as rough idling, stalling, and a noticeable drop in fuel efficiency. These performance issues not only make your driving experience less enjoyable but can also pose safety risks on the road. Furthermore, if left unaddressed, a vacuum leak can cause damage to critical components like the oxygen sensors and catalytic converter, resulting in costly repairs down the line. Over time, the effects of a vacuum leak can escalate, potentially leading to more serious mechanical failures that could jeopardize the reliability and safety of your vehicle. Therefore, it is crucial to prioritize the repair of any vacuum leaks to maintain optimal performance and prevent further damage to your 2018 Mitsubishi Mirage.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.

2018 Mitsubishi Mirage Vacuum Leak Repair Guide | RepairPal