Water Dripping From Exhaust Manifold: Hidden Causes Behind the Issue

Water dripping from your car’s exhaust manifold can be caused by a few different issues. 

Determining the exact cause is vital to fix the problem.

Possible Causes for the Issue

Condensation Buildup

How Condensation Occurs

• Condensation buildup is the most common reason for you to be aware of this issue. 

• Condensation forms when hot exhaust gases meets the colder outside temperatures at the engine start-up. 

• The rapid change in temperatures causes water vapor to condense and collect in the exhaust system. 

• Over time, enough condensation can build up and will drip out when the car is shut off.

Preventing the Condensation Buildup

There are a few ways that helps you to prevent excessive condensation buildup:

• Avoid short trips – Short drives do not allow the exhaust system to fully heat up and evaporate any accumulated moisture. Take your car on longer drives to dry things out.

• Check your thermostat – A faulty thermostat or a broken thermostat can prevent the engine from reaching the optimal operating temperature by leading to a growth of the condensation.

Fixing Condensation Issues

If condensate is dripping excessively from the exhaust manifold you can try these steps:

• Improve the ventilation – Allowing more airflow under the car can help to moisture the evaporative bubbles rather than collecting those.

• Install exhaust wraps – Exhaust wraps can help to insulate the system by allowing it to retain more heat to evaporate and start the condensation process.

Leaking Intake Manifold Gaskets

• Intake manifold gaskets create a seal between the intake manifold and the engine cylinder heads. 

• Over time, these gaskets can fail by causing an external coolant or internal combustion of air leaks.

Identifying the Leaking Manifold Gaskets

Symptoms that can indicates a leaking intake manifold gasket includes:

• White smoke coming out from the exhaust – This smoke is usually sweet-smelling and indicates that the coolant is leaking into the combustion chambers where it burns off as steam through the exhaust.

• Engine overheating – Leaks can lead to losing the coolant by causing the engine to run much more hotter.

• Water dripping from below the intake manifold – Coolant may pool near the leak and drip down when the engine is warm.

• Oil dripping from the exhaust manifold – If the leak allows the coolant into the engine cylinders, it can seep into the oil and then get burned out through the exhaust. This will give the exhaust a chance to be visible as an oil-like appearance.

You may also notice rough engine idle, loss of power, and difficulty of starting if the leaks are significant. 

Having the vehicle diagnosed to confirm the leak source is recommended.

Replacing the Leaking Gaskets

Steps to replace a leaking intake manifold gasket:

• The intake manifold itself and other components like fuel rails, sensors, ignition coils, etc. will need to be removed to access the gaskets. 

• This requires disconnecting electrical connectors, fuel lines, vacuum hoses, and more of the components.

• The cylinder head and the manifold mating surfaces may needs scraping to clean and remove any old gasket material and debris. These surfaces must be completely clean for proper sealing.

• Apply gasket sealant if recommended by the manufacturer. Make sure to install the new gasket set as per the precise specifications. This is because, proper torque values for manifold bolts are critical when reassembling.

• All electrical, vacuum lines, sensors and other components must be reinstalled. 

This is typically a lengthy repair, which takes 3-6 hours of shop labour. Gasket sets can range from $60-150 or more, depending on the vehicle.

FAQs About Water Dripping from Exhaust Manifold

Q: Is a small amount of water drainage is normal?

A: A small amount of water drainage from the exhaust manifold is fairly normal, especially when an engine is first started, and then rapidly the exhaust temperature changes to condensation buildup to occur. 

Q: What colour might be the dripping liquid?

A: Most often, leaking manifold drips will looks slightly rust-coloured. However, coolant contains ethylene glycol, so as a result, it will be either green or neon.