Where Is The Crankcase Sensor Located?


The crankcase sensor plays a pivotal role in detecting the amount of overpressure with the engine oil of the crankcase. Overpressure issues take place due to diesel leakage from the engine oil. Let us dive deeper into the crucial car component and how it is linked to the crankcase.

What Exactly is a Crankcase Sensor?

A crankcase lies in the internal combustion engine and keeps the crankshaft within it. Most of the present-day vehicles come with a pre-installed engine block. Two-stroke engines use the crankcase compression design, allowing the air to fuel mixture to pass through the crankcase before entering the cylinders. In the case of 4 stroke engine, there is an oil sump that is present below the crankcase, and the space, also known as the crankcase pressure sensor, holds the maximum amount of oil here.

In most of the vehicles, the crankcase has been the lower half section of the main bearing journals, while bearing caps are the other half-section. The main bearing journals hold the crankcase and camshaft, thereby helping them move freely within the engine. Determine the crankcase sensor location so that it can be inspected accordingly.

Role of Crankcase Ventilation System


A crankcase ventilation system eradicates unwanted gases or excessive gases from the crankcase. By doing this, the crankcase is generally prevented from misreadings. It consists of a tube, one-way valve, and vacuum tube, which is similar to the intake manifold. The cylinders are generally supplied with fuel is to air mixture via the intake manifold. The modern vehicles have PVC(Positive Ventilation Camshafts) that deliver crankcases back to the combustion chambers that minimize air pollution and surges fuel efficiency within the car. The air moving within the crankcase gets rid of byproducts and unwanted gases.

What Exactly Is a PO51B Code?

Present-day vehicles are connected with the car’s computer that helps the vehicle perform optimally. You can determine the problems by reading the crankcase sensor code on the dashboard. These trouble codes are commonly found on brands like Ford, Dodge, Ra, Jeep and Fiat, and many other vehicles. Ensure that the computer gives accurate readings as not doing so would damage the seals and gaskets of the car. Also, the fumes need to be delivered back to the system using a positive crankcase ventilation system.

What are Some of the Bad Crankcase Sensor Symptoms?


We have compiled a list of bad crankcase sensor symptoms the moment one identifies the PO51B code:

Reduced Gas Mileage

You would notice a decrease in your gas mileage while there are troubles with the crankcase sensor. This means the gas within the car needs to be filled quite often. This would minimize the fuel efficiency and degrade the performance of your vehicle.

Gasket Leaks

Gasket leaks are another crankcase sensor problems that need the attention of the driver. Gasket leak leads to numerous issues in the car, and the major one is the coolant loss which makes the water and pressure erosion within the engine block.

Strong Smell of Oil & Fuel

You would notice a strong smell of fuel and oil within the exhaust. Drivers would easily notice the smell and tell there was something wrong with the car. Get a necessary inspection from the mechanic and get the crankcase position sensor replaced if the condition becomes worse.

Rough Engine Idling

Your engine won’t work smoothly due to rough engine idling. Rough engine idling occurs due to numerous reasons: dirty fuel injectors, clogged air filters, and bad or damaged spark plugs, possibly due to exhaust issues.

Engine Oil Getting Thick

The engine oil starts getting thick due to the accumulation of dirt and debris. This can give rise to pressure sensor issues and is the leading cause of damaged pressure sensors.

Black Smoke Released by the Car

If you notice black smoke from the exhaust, it is because of a bad crankcase sensor. If such things happen, you will notice discrepancies in the readings of the sensor. Inspect the following symptoms in the vehicle and get the crankcase position sensor replaced by the mechanic.

How Much Does Crankcase Position Sensor Cost?

Investing in a new crankcase pressure sensor would be the best option in case of a problematic sensor. If replacement is an expensive affair for you, get a quality part at an affordable price from a trusted store like ‘The Auto Parts Shop’ and pay the labor charges to the mechanic. A timely replacement would save the engine from issues later on. Installation isn’t carried out using specific methods and ensures that testing is performed once the sensor is fitted within the car.

The Replacement Cost Of The Positive Crankcase Ventilation System


At times there are issues with the positive crankcase ventilation system and needs to be replaced for proper air is to fuel supply and maintain optimum ratios. The PCV system of the BMW 2007 Z4 is $195, while $88 is the cost of parts, and $80 is paid to the labor. A 2014 Infiniti WX70 cost is a little more at $195.69, the cost of parts is $80.

The Bottom Line

Issues related to crankcase sensors mustn’t be taken lightly, and crankcase position sensor replacement should be taken seriously to prevent other components from damage.

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