Owning a Porsche Boxster is a truly fun experience whether you drive it daily or get it out on the open road. But, if you start to see smoke coming from the exhaust, it can be cause for concern. Reasons for smoke vary greatly from being just commonplace and nothing to worry about to being significant and needing a mechanic’s attention.

Many times the color of the smoke can be a good diagnostic tool to help you in determining what is causing it. Blue smoke upon startup is not uncommon when the car has sat idle for a while. White smoke coming from the tailpipe can also be a common occurrence when the engine is started due to a build-up of condensation. You may see black smoke coming out of the exhaust when starting but then clearing up after the engine warms.

However, when any color of smoke continues after the car warms up, you may have cause for concern.

Reasons Why Your Porsche Boxster is Smoking

Here are some possible reasons why your Porsche Boxster is smoking.

Air-Oil Separator

A failure in the air-oil separator (AOS) can be a likely culprit in causing your Boxster to smoke. The AOS is a device that is designed to reduce your car’s emissions. When the AOS fails, it can result in oil going into the intake manifold, which then causes damage to spark plugs and catalytic converters. Sometimes, but not always, a failure in the AOS can cause the Check Engine Light to come on.

The more common symptom is a large amount of white smoke coming from the exhaust and the engine running rough. When you have a faulty AOS, it is not removing all of the oil vapor and, as a result, leaves oil on the intake walls. When the engine is shut off, this oil runs down into a cylinder and smokes upon the next engine start.

Clogged or Dirty Air Filter

The air filter is an essential part of your vehicle’s fuel system that prevents airborne contaminants from getting into the car’s engine. When the air filter is clogged up, this dirt can get to your car engine and cause smoke. After changing the air filter, if you continue to see smoke, it may be due to an irregular air-to-fuel ratio.

Air-to-Fuel Ratio is Off

The Porsche Boxster may have an uneven air-to-fuel ratio that is causing the car to burn more fuel than air. Two common reasons for this are a malfunctioning fuel pressure regulator or leaky, clogged fuel injectors.

Bad Fuel Pressure Regulator

When the fuel pressure regulator is not working properly, the pressure can fluctuate outside of the defined range. If the pressure is too low, there may not be enough fuel making its way to the engine for starting it. If the pressure is too high, your car may have over-fueling, which causes the engine to run rough.

Leaky or Clogged Fuel Injectors

If your Boxster has fuel injectors that are not functioning properly because they are leaky or clogged, your car can have black smoke coming out from the exhaust. When working properly, the fuel injectors spray a specific amount of atomized gas into the vehicle’s intake manifold, which then goes into the combustion chamber and mixes with a predetermined amount of oxygen.

This optimizes the efficiency of the combustion.

Blown Head Gasket

If your Porsche Boxster has white smoke that continues after start-up, it’s possible that it is burning coolant that has leaked into the combustion chamber from a blown head gasket. The head gasket is between the engine block and the cylinder head and seals the connection.

So, if the head gasket is damaged, coolant gets into the combustion chamber. This is costly, but it is fixable.

Damaged Cylinder Head

A cracked or warped cylinder head causes the engine to lose compression and misfire because there is too much heat. When the heat reaches a point of causing the cylinder head to crack because components have warped, you need to replace the entire head.

Cracked Engine Block

If your Boxster is emitting white smoke continuously, not just when starting the engine, it’s possible that you have a cracked engine block. This is very serious and impossible to repair.

Malfunctioning Valve Stem Seal

The valve stem seal regulates the amount of oil that is applied to the valve stem interface, which ultimately lubricates the combustion chamber. For this issue, you will see blue-grey smoke after sitting at a stop for 30 to 60 seconds and then beginning to throttle. The solution to a malfunctioning valve stem seal is to either replace the seal or rebuild/replace the engine.

Failed Piston Rings

Having failed piston rings is a rare occurrence, but it can happen. When it does, your Boxster will emit blue or gray smoke during heavy acceleration, which indicates that oil is leaking into the engine’s combustion chamber.

Contact Triangle Imports for Porsche Service

When you experience smoke from your Porsche Boxster it may be common or it could be serious! Contact our team at Triangle Imports for expert diagnosis of the issue at hand.