Constant Pressure Valve

Many people get stumped and most are unaware of the constant pressure valve which is fitted at the back of the the M3 block. This valve can and often does begin to weap oil and them progress into a constant leak. You may see a leak underneath the car but may be unaware of where it is coming from. In lots of cases you will also see oil burning smoke from the left had side of the engine bay as this oil drips onto the exhaust system. It is a cheap part to purchase from BMW, approx £20 but can be a difficult job to remove as it will often need the application of heat to remove. Access is also limited and it may require the removal of the exhaust manifold to aid accessibility..