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Porsche Exhaust System Questions

Does your Porsche have an exhaust leak? Or, is it belching thick black smoke for a few seconds on the first start? These are some problems which Porsche owners encounter to which they need reliable solutions. If you have an exhaust problem and don’t know what’s causing it, your best bet is to ask an Expert.

Read on to see how Experts have helped owners overcome exhaust problems by answering their questions.

Why is a Porsche Cayenne exhaust system exceptionally loud?

This could be caused for multiple reasons, some of them being a cracked manifold, failing gasket or some other exhaust related failure. The best way to determine the cause is to put the vehicle on a lift so it can be inspected.

What does white smoke from a Porsche Cayman exhaust signify?

White smoke from the exhaust generally suggests that the engine is burning coolant or oil. If coolant is leaking into the engine its presence is generally visible if the oil is examined. In this case, it is more likely to be a piston ring issue. A thumb rule to support this diagnosis is that oil leaking past worn piston rings belches thick white smoke for as long as the car is accelerating hard. The emission ceases once the accelerator is released.

What does thick blue smoke from a Porsche Carrera exhaust signify?

Blue smoke from the exhaust generally suggests leaking valve seals which allow oil to leak onto the pistons and into the cylinders. The smoke is emitted immediately after accelerating hard but not when running at a consistent speed.

What do codes P0420 and P0430 on a Porsche Carrera mean?

Both these codes refer to exhaust leaks, which could be on either side of the catalytic converters, or to failed oxygen sensors.

What does about four seconds of black smoke first thing in the morning from a Porsche Cayenne exhaust indicate?

Black smoke is an indication of raw fuel burning. It could be caused by a leaking fuel injector which drips overnight or continues to drip when shut off. When this happens raw fuel pools in the cylinder till the engine is started, when it is burned and blown out of the exhaust, partially burned. Since there is a flood of fuel it is not able combust completely in the combustion chamber and continues to burn as it passes through the exhaust, being expelled as a few seconds of concentrated black smoke. The solution is to clean the fuel system and all injectors though only one may be faulty. It would also be advisable to replace the fuel filter. To identify the faulty injector remove the spark plugs before starting the engine in the morning and check each cylinder for a strong smell of pure fuel.

How can oil be flushed out of an exhaust system which belches out a large amount of thick black smoke?

The best way is to burn off the oil deposits. Get the exhaust heated up fast and run the car at a consistently high speed, for as long as possible, till the exhaust has stopped smoking. Once the catalytic converter is heated sufficiently it should burn residual oil and soot without difficulty.

Why do fuel fumes enter the cabin of a Porsche Carrera when driving?

The fumes are coming from the exhaust system. Check for leaks in all fuel lines, the catalytic converter and both intake and exhaust manifolds. Also, check the gas evaporator which looks much like a charcoal filter.

How does a broken catalytic converter impact exhaust gases?

The catalytic converter is designed to clean three harmful emissions from exhaust gas: carbon monoxide, oxides of nitrogen and unburned hydrocarbons. A broken catalytic converter will no longer do this and, if dislodged and wedged in, could also lead to back pressure of combustion gases in the exhaust system. This in turn would impact engine power and cause the engine to misfire. Additionally, the check engine light will inevitably come on setting error codes which reference catalyst deficiency.

The exhaust system primarily vents out exhaust gases. But it also serves to reduce harmful emissions and, through the built in muffler, contain noise. Exhaust problems are often a symptom of some other underlying issue so it’s important to read them correctly. If you have an exhaust malfunction and don’t know how to proceed, ask an Expert for help. Experts are there to answer questions on all Porsche exhaust issues.

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