When Should You Replace the PCV Valve in Your Mini?

Red Mini Cooper Car

MINIs have been vehicles which have captured the hearts of nation after nation. Not afraid to put the fun back into motoring, their bright and customizable colours are attractive to those wanting to express their unique personality. One of the best things about a MINI is that underneath that fun exterior is a quality car that is built to last.

However, even the funkiest but durable of cars stops being fun when it becomes a pain to drive. Poor maintenance can lead to all manner problems. In this article, we will take a closer look at your MINI’s PCV valve, what it is, and when it is best to replace it.

What is a PCV valve?

The PCV valve is a system invented in the 1960s as a solution for blow-by gases released by a vehicles engine. Blow-by gases are the unburnt fuel that has leaked from the engine. These gases are full of all manner of toxic substances, which if not removed from the vehicle will eat away at the inside of your car.

The PCV valve, which stands for Positive Crankcase Ventilation, is a system which sucks the unspent fuel out of the crankcase back to the intake manifold and then back to the engine to be fully burned. Think of it as a recycling fuel.

Without this valve operating properly, dangerous blow-by gases are allowed to run rampant inside your engine, potentially causing thousands of dollars of damage and potentially making your entire MINI a complete write off.

When should you replace the PCV valve?

The PCV valve has a filter, which it uses to catch the toxins in the fuel before it is re-supplied to the engine. This filter is what most commonly needs replacing. On average, it is recommended you replace the PCV valve filter every 60,000 miles. However, it should certainly receive proper maintenance within this timeframe. The valve itself has no specific time frame of replacement. It should simply be repaired and/or replaced as needed. Your trusted MINI mechanic can keep diligent watch over this part and notify you when it is time to replace it. As with the valve, the filter should be replaced when it shows signs of failure.

Signs of PCV Valve Failure

There are two ways in which the PCV valve can fail and require replacement. The first being if the filter becomes clogged, the second being the failure of the valve mechanism.

Filter Failure

The most common signs of a clogged PCV valve are:

  • An increase in the internal engine pressure
  • Failed seals or gaskets
  • Engine oil leaks
  • Black smoke emissions
  • A build up of sludge in and/or around the engine
  • Moisture under the hood
  • Unexpected engine surges
  • Misfiring engine (due to the lean mix of air and fuel)
  • Oil found in the MAF sensor
  • Increased and inefficient oil consumption

Of course, many of these symptoms can also be signs of other issues with your MINI. However, if you notice any of these problems, it is definitely worth taking the time to check if the MAF sensor filter is at fault.

Stuck Valve Issues

Like with the filter, this can sometimes be difficult to diagnose, often masking itself as a MAF system failure, which often leaves drivers assuming they have an issue with the air-to-fuel ratio in their engine. Noting some of the signs and symptoms below can help you to correctly diagnose whether the PCV valve is stuck.

  • Engine misfire, particularly when idle
  • Poor air-to-fuel ratio
  • Engine oil in the valve
  • Increased oil consumption
  • Difficult engine ignition
  • Rough idling

Replacing the PCV Valve

As it is crucial to the smooth running of your MINI Owner Mechanic Discussion engine and the overall health of the inside of your MINI, unless you have mechanical knowledge, it isn’t advisable to attempt repairs yourself. You should always seek professional help for repair or replacement of the PCV valve. However, unlike some of the systems it can damage, replacing the valve is typically a relatively cheap maintenance job, usually costing under $100, unless there are mitigating factors.

For PCV valve repair by a team you can trust, look no further than Mike Johns Imports. We are specialists in imported cars. Your MINI really couldn’t be in safer hands. Call or come by today for consultation or to make an appointment for service.

* Red Mini Cooper Car image credit goes to: bruev.

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