Mini is a household name, evoking feelings of fun and freedom in a pint-sized form. Minis are available in a variety of colors and iterations of the classic design. They have captured the hearts of generations. Best of all, under their fun exterior, the Mini has a serious motor with quality parts that are made to last.
However, regardless of the manufacturer’s high standards, without the correct care and maintenance, even the most well-constructed cars can start to malfunction and fail. In this article, we will explore the PCV valve and discuss what it is, what it does, and when you should replace it.
What is the PCV Valve and What Does it do?
Invented in the same decade as the Mini, the PCV (Positive Crankcase Ventilation) valve is a system that constitutes the solution to the hazardous blow-by gasses that an engine releases. Blow-by gasses are vapors of unburnt fuel. They are laced with toxic substances that have the ability to quite literally eat away at the inside of your car if not successfully ventilated.
The PCV valve itself is found under the hood. It is black with a red handle attached. The valve is responsible for sucking the unspent fuel (blow-by gas) out of the crankcase, through the intake manifold, and finally back to the engine where it can be burnt through fully.
If the PCV valve has failed, then these toxic fumes remain stuck in your engine, causing untold damage.
When Should the PCV Valve be Replaced?
It often isn’t the valve itself that becomes worn. Instead, the filter in the PCV valve will often need replacing. This filter is used to trap the toxins in the partially-burnt fuel before it can be resupplied to the engine. Because it deals with the damaging toxins directly, the filter can become clogged or worn out.
In general, mechanics recommend that the PCV valve is replaced every 60,000 miles. Within this time frame, it should also be regularly serviced. The valve itself does not have a specified timeframe for replacement and should be replaced or repaired as needed.
Symptoms of PCV Valve Failure
Typically, there are two ways in which PCV valve failure can occur, either through the failure of the filter or through the failure of the valve mechanism itself. It is typically easy to determine which element is causing your Mini trouble through the symptoms they present.
- Increased internal engine pressure
- Failure of gaskets or seals
- Engine oil leaks
- Black, smoky emissions
- Sludge build up in or around the engine
- Moisture under the hood
- Engine surging unexpectedly
- Lean misfires
- Oil in the MAF sensor
- Increase in oil consumption
If you notice any of these issues, it is best to first check if the MAF sensor is functioning correctly. Once this is ruled out, it is likely the PCV filter is to blame.
A Stuck Valve
A stuck PCV valve can be mistaken for a MAF failure and vice versa. Once this is ruled out, and if you are still suffering from the symptoms listed below, then it is likely your PCV valve has been stuck in the open or closed position.
- Engine that misfires, particularly when idling
- A bad air-to-fuel ratio
- Engine oil in the PCV valve
- An increase in oil consumption
- Engine struggles to ignite
- Rough idling
Replacing the PCV Valve or Filter
Unless you have professional knowledge, it is not advisable to undertake PCV valve replacement on your own, as it has such an integral role to play in regards to the overall health of your car’s engine.
However, the good news is that so long as you don’t delay, PCV valve maintenance at Bavarian Auto is typically fairly inexpensive, unless there are mitigating factors. This low cost is but a drop in the ocean when compared to the damage that an inoperational PCV valve can cause, which can easily reach into the thousands of dollars instead.
If you are worried about the status of your PCV valve or filter, call us today. If you live in or around Ootelwah, Hixson, or Chattanooga, TN, stop by Bavarian Auto for the very best in vehicle servicing and repair.
* Mini Cooper Countryman image credit goes to: bruev.