[9t2hoo]

I just got a letter from BMW extending the warranty for the engine crankcase pressure control valve out to 15 years. Interestingly the symptoms described in the letter for when the valve fails are exactly the same as the symptoms I experienced with a failed turbo this past summer. Does anyone know if the PCV is related to the turbo? Could a failed PCV cause the turbo to fail? Thanks for your help.

[Nickies]

I received the same letter specific to my serial number. This is not a recall.

[JMcLellan]

Same thing for me. Got the letter last Friday. Forwarded the info to the new owner.

I believe there are cases of the PCV failing and causing turbo and engine failures.

[Mike F.]

Got my letter today. PCV failure leading to a turbo failure sounds doubtful to me, but my overall knowledge of such things is somewhere between dismal and non-existent. Hopefully, someone who knows about this sort of thing can comment.

[jzeiler4]

PVC valve is more of an emissions thing i.e. positive crankcase ventilation.

It controls the amount of crankcase vapors that get sent to the induction system to be burned during normal running rather than expelled into the air. When it fails it sucks more than it should resulting in excess oil vapors being burned, thus smoke in the exhaust.

Pre 1960 there was just a tube in the rocker cover that let the vapors just go into the air just below the engine.

[Frosty]

[Frosty]

https://bmwtuning.co/the-5-most-comm...gine-problems/

".....

PCV Valve Failure
The PCV valve, or positive crankcase ventilation valve, is an important component that plays a vital role in equalizing pressure within the B58’s crankcase. Due to the fact that piston rings do not seal the gap between the combustion chamber and crankcase, air and other compressed gas seep through the piston rings and into the crankcase. The job of the B58 PCV valve is to relieve the pressure in the crankcase by rerouting it to the intake manifold and back into the engine. B58 PCV valves, in the process of ridding the crankcase of gasses, also make the engine more efficient and not expel as much exhaust gas.

Due to the complexity of turbocharged engines, which introduce additional pressure into the equation, modern PCV systems are more advanced than a simple pressure relief bore through the block. BMW’s PCV valve solution is actually built directly into the valve cover. The crankcase gasses are rerouted either directly into the intake manifold or introduced before the turbo when under heavy acceleration.

Where the gasses end up is dictated by a diaphragm in the PCV system. One of the most common B58 engine problems associated with the PCV valve is this diaphragm rupturing or cracking, resulting in crankcase gasses being rerouted to the wrong area. This can result in oil-rich gasses being pumped into the intake manifold.

BMW B58 PCV Valve Failure Symptoms
Smoke coming from the exhaust
Timing issues
Engine running either lean or rich
New or worsening oil consumption
Poor engine performance
When your BMW B58’s PCV valve fails, or is nearing failure, one of the most common symptoms is smoke coming from your exhaust. There are countless videos of B58 BMW owners with this exact symptom resulting from a damaged PCV. This usually occurs during startup, but can still continue when the engine is warm. Excessive oil consumption is another big one that can alert you to this issue. However, it can be hard to catch with this symptom alone, as the B58 also has other oil consumption issues.

BMW B58 PCV Valve Failure Fix
If you wanted to go the traditional route and bring your B58 BMW to a BMW-certified center for repairs, they will likely say that the entire PCV-integrated valve cover will need to be replaced. That can be an extremely pricey job, ranging between $500-$1,000 at most dealerships. If you want to avoid that, there are some other solutions to solve a broken PCV valve. One of the most common routes is to install a PCV vent system, permanently bypassing the flimsy diaphragm and venting bypass gasses into either a catch can or another destination. Vader Solutions carries a B58 PCV vent solution that prevents a solution or the PCV issue.

...."

[mecheng77]

What engine is this for?

[Dom147]

Originally Posted by mecheng77

What engine is this for?

It's for the b58