BMW E36/E46 3 Series & Z3 M43/M44 Replacement Crankcase Breather Hose & PCV Vent Valve – Restore Proper Crankcase Ventilation, Reduce Vacuum Leaks & Improve Engine Idle | Replaces Part No. 11157501567 / 11151743386

Restore proper crankcase ventilation and help eliminate unwanted vacuum leaks with this replacement crankcase breather hose and PCV vent valve designed for select BMW E36 and E46 3 Series and Z3 vehicles equipped with M43 and M44 four-cylinder gasoline engines. The crankcase ventilation system, commonly referred to as the positive crankcase ventilation (PCV) or crankcase breather system, plays an essential role in regulating internal engine pressure, directing combustion blow-by gases back into the intake system, and preventing excessive pressure buildup inside the engine. Maintaining a properly functioning PCV valve and breather hose is important for stable engine idling, correct air-fuel mixture control, and the long-term reliability of engine seals and gaskets.

As factory crankcase ventilation components age, continuous exposure to engine heat, oil vapors, pressure fluctuations, and normal vibration can cause the breather hose to become brittle, develop cracks, or deteriorate around its connection points. The PCV valve can also experience internal wear, diaphragm deterioration, or contamination from accumulated oil residue. These problems may interfere with proper crankcase pressure regulation and allow unwanted air to enter the intake system. Common symptoms include rough idling, fluctuating engine speed, whistling or hissing noises, increased oil consumption, oil leaks around engine seals, and lean air-fuel mixture fault codes.

This replacement crankcase breather hose and PCV valve combination is designed to restore the intended ventilation pathway between the engine crankcase and intake system. The PCV valve helps regulate the movement of blow-by gases according to engine operating conditions, while the connected breather hose provides a sealed passage for crankcase vapors. Replacing a malfunctioning valve and deteriorated hose can help correct vacuum leaks, restore appropriate crankcase pressure, and reduce drivability problems associated with a failing ventilation system.

Designed around the factory crankcase ventilation components associated with BMW part numbers 11157501567 and 11151743386, this replacement combination provides a factory-style solution for compatible BMW four-cylinder engine applications. The valve and hose are separate components that perform complementary functions within the ventilation system. Correct installation, secure connections, and properly seated seals are essential for maintaining the intended crankcase pressure regulation and preventing additional intake air leaks.

For aging BMW E36, E46, and Z3 vehicles, replacing deteriorated crankcase ventilation components is an important maintenance procedure that can help preserve engine refinement and reliability. The M43 and M44 engine families rely on effective crankcase ventilation to manage blow-by gases and maintain appropriate internal pressure. Addressing worn breather hoses and malfunctioning PCV valves before they cause more extensive problems can help reduce pressure-related oil leaks, improve idle quality when ventilation faults are present, and protect surrounding engine components.

Key Features

• BMW M43/M44 Engine Compatibility: Designed for select BMW E36 316i, 318i, 318is, 318ti, E46 316i/318i, and Z3 applications equipped with compatible four-cylinder gasoline engines and the corresponding crankcase ventilation configuration.

• Restores Proper Crankcase Pressure Regulation: Helps maintain the intended movement of blow-by gases from the engine crankcase into the intake system, reducing abnormal pressure conditions caused by a restricted or malfunctioning ventilation valve.

• Helps Eliminate Vacuum Leaks: Replacing a cracked breather hose or leaking PCV valve can eliminate unmetered air entering the intake system through damaged crankcase ventilation components.

• Supports Stable Engine Idling: Correcting crankcase ventilation air leaks may help reduce rough idling, fluctuating engine speed, and engine stumbling when the original valve or hose is responsible.

• Helps Reduce Excessive Oil Consumption: Restoring proper crankcase ventilation may reduce oil consumption associated with abnormal crankcase pressure or excessive oil vapor entering the intake system.

• Supports Accurate Air-Fuel Mixture Control: Maintaining sealed crankcase ventilation connections helps prevent unwanted air from disrupting the engine management system's fuel mixture calculations.

• Helps Prevent Pressure-Related Oil Leaks: Proper crankcase pressure regulation can reduce unnecessary stress on engine seals and gaskets that may otherwise develop or worsen oil leaks.

• Factory-Style Replacement Configuration: Intended to replace the corresponding original BMW crankcase ventilation valve and breather hose while maintaining the factory ventilation arrangement.

• Addresses Common Aging-Related Ventilation Problems: Suitable for replacing components affected by cracked hoses, brittle connections, internal valve deterioration, damaged diaphragms, or accumulated oil residue.

• Important Preventive Engine Maintenance: Inspecting and replacing failing crankcase ventilation components can help prevent recurring vacuum leaks, unstable idling, and pressure-related engine problems.

Restore the smooth, consistent engine operation of your BMW with a replacement crankcase breather hose and PCV valve designed to maintain proper ventilation flow and crankcase pressure regulation. Replacing deteriorated components can help reduce vacuum leaks, improve idle stability, minimize pressure-related oil leakage, and support accurate air-fuel mixture control. For older BMW four-cylinder engines, maintaining the crankcase ventilation system is an important step toward preserving dependable engine operation and long-term reliability.

FITMENT: BMW E36/E46 3 Series & Z3

Compatible with select BMW E36 and E46 3 Series and Z3 models equipped with M43, M44, and certain M42 four-cylinder gasoline engines using the corresponding crankcase ventilation valve and breather hose configuration.

BMW E36 3 Series Sedan (Approximately 1993–1998)

• BMW E36 316i – M43B16 1.6L Engine
• BMW E36 318i – M43B18 1.8L Engine
• BMW E36 318i – M42B18 1.8L Engine, select applications
• BMW E36 318i – M44B19 1.9L Engine, select applications

BMW E36 3 Series Coupe (Approximately 1993–1999)

• BMW E36 316i Coupe – M43B16 1.6L Engine
• BMW E36 318is Coupe – M42B18 1.8L Engine
• BMW E36 318is Coupe – M44B19 1.9L Engine

BMW E36 3 Series Compact (Approximately 1994–2000)

• BMW E36 316i Compact – M43B16 1.6L Engine
• BMW E36 316i Compact – M43B19 1.9L Engine
• BMW E36 318ti Compact – M42B18 1.8L Engine
• BMW E36 318ti Compact – M44B19 1.9L Engine

BMW E36 3 Series Touring (Approximately 1995–1999)

• BMW E36 316i Touring – M43B16 1.6L Engine
• BMW E36 318i Touring – M43B18 1.8L Engine

BMW E46 3 Series Sedan (Approximately 1998–2001)

• BMW E46 316i – M43TU 1.9L Engine
• BMW E46 318i – M43TU 1.9L Engine

BMW E46 3 Series Touring (Approximately 1999–2001)

• BMW E46 318i Touring – M43TU 1.9L Engine

BMW E46 3 Series Coupe (Select 1999–2001 Applications)

• BMW E46 316Ci – M43TU 1.9L Engine
• BMW E46 318Ci – M43TU 1.9L Engine

BMW Z3 Roadster E36/7 (Approximately 1995–2002)

• BMW Z3 1.8 – M43B18 1.8L Engine
• BMW Z3 1.9 – M43TU 1.9L Engine
• BMW Z3 1.9 – M44B19 1.9L Engine

Important Fitment Information

BMW parts-catalog cross-references identify crankcase ventilation valve 11157501567 and breather hose 11151743386 across E36, E46, and Z3 applications. However, the two components have separate application records, and compatibility with one does not automatically establish compatibility with the other.

The listed production years are approximate vehicle application ranges rather than guarantees that both components fit every vehicle produced during those years.

Certain M42-powered BMW E36 models are also associated with the referenced PCV valve. However, their breather hose configuration should be verified separately.

Exact compatibility depends on the vehicle's engine code, production date, crankcase ventilation arrangement, and original BMW part numbers.

Engine Compatibility

• BMW M43 Engine Family: Four-cylinder gasoline engines used in select BMW E36, E46, and Z3 applications.
• BMW M43TU Engine Family: Updated four-cylinder gasoline engines used in select later BMW E36, early E46, and Z3 applications.
• BMW M44 Engine Family: Four-cylinder gasoline engines used in select BMW E36 318i, 318is, 318ti, and Z3 1.9 applications.
• BMW M42 Engine Family: Earlier four-cylinder gasoline engines used in select BMW E36 applications with corresponding crankcase ventilation components.

Applicable Engine Variants

• BMW M43B16 – 1.6L Four-Cylinder
• BMW M43B18 – 1.8L Four-Cylinder
• BMW M43B19 – 1.9L Four-Cylinder
• BMW M44B19 – 1.9L Four-Cylinder
• BMW M42B18 – 1.8L Four-Cylinder, select applications

OEM Replacement Part Numbers

• 11157501567 – Crankcase Ventilation Valve / PCV Valve: Regulates crankcase ventilation flow and helps maintain appropriate crankcase pressure.
• 11151743386 – Crankcase Breather Hose: Provides the corresponding ventilation connection for crankcase gases within compatible engine configurations.

Previous BMW Part Numbers

• 11151247133 – Previous Crankcase Ventilation Valve: Superseded by BMW part number 11157501567.
• 11151247743 – Previous Breather Hose: Listed as a predecessor to BMW part number 11151743386.
• 11151739547 – Earlier Breather Hose Reference: Listed in BMW parts-catalog supersession records, with restrictions concerning retrospective interchangeability.
• 11151739231 – Earlier Breather Hose Reference: Associated with the corresponding BMW breather hose replacement family.

BMW parts-catalog information confirms the supersession from 11151247133 to 11157501567. It also identifies earlier hose references associated with 11151743386, although some historical hose revisions have interchangeability restrictions.

Additional Engine Compatibility Information

Although the M42, M43, M43TU, and M44 engines use related crankcase ventilation principles, individual component configurations can differ.

The M43 engine family generally uses a crankcase ventilation arrangement with a pressure-regulating valve and corresponding ventilation connections.

The M44 engine family also uses crankcase ventilation components that regulate crankcase gases, but hose routing and component arrangements may differ from M43 applications.

The later BMW N42 and N46 engines use different crankcase ventilation configurations and should not automatically be considered compatible with these components.

Customers should verify both replacement part numbers individually rather than relying exclusively on the engine family or vehicle model.

Installation

• Factory-style replacement crankcase breather hose and PCV ventilation valve for compatible BMW four-cylinder gasoline engines.
• Professional installation is recommended, particularly when the source of a crankcase ventilation leak has not been confirmed.
• Allow the engine to cool completely before beginning the replacement procedure.
• Locate the original crankcase ventilation valve and associated breather hose connections within the engine compartment.
• Remove any necessary engine covers, intake ducting, or surrounding components required to access the existing ventilation assembly.
• Inspect the original breather hose for cracks, hardened sections, loose connections, oil residue, or other signs of deterioration.
• Inspect the PCV valve and surrounding connections for damaged seals, accumulated deposits, or evidence of vacuum leakage.
• Carefully disconnect the original breather hose from its corresponding engine and ventilation valve connections.
• Use caution when removing aged plastic fittings and connectors, as prolonged exposure to engine heat can make these components brittle.
• Remove the original crankcase ventilation valve according to the appropriate BMW service procedure.
• Inspect the valve mounting location and surrounding sealing surfaces for contamination, deterioration, or damage.
• Compare the replacement PCV valve and breather hose with the original components to confirm the correct mounting configuration, hose length, connection diameter, and overall arrangement.
• Clean the appropriate mounting surfaces and ventilation connections before installing the replacement components.
• Inspect the required O-rings, gaskets, and sealing components, replacing them when specified by BMW service documentation.
• Install the replacement PCV valve in the corresponding factory mounting location.
• Ensure the valve is properly positioned and that all applicable sealing components are correctly seated.
• Connect the replacement crankcase breather hose to the appropriate ventilation valve and engine connections.
• Ensure the hose is fully seated without twisting, kinking, or excessive tension.
• Secure all connections using the appropriate factory retaining clips, clamps, or fittings.
• Route the replacement hose according to the original configuration, avoiding contact with moving components, sharp edges, and high-temperature engine parts.
• Reinstall any intake ducting, engine covers, or surrounding components removed during the replacement procedure.
• Tighten all mounting hardware according to the correct BMW specifications for the specific engine and chassis.
• Start the engine and check for abnormal whistling noises, rough idling, visible oil leaks, or signs of improper crankcase ventilation.
• Inspect the replacement hose connections for vacuum leaks and verify that the engine idles normally.
• If rough idling or lean-running fault codes persist, inspect the remaining intake system and crankcase ventilation connections.
• Perform an appropriate intake smoke test or crankcase pressure test when necessary to confirm that the ventilation system is operating correctly.

Replacing a mechanical PCV valve and breather hose does not ordinarily require engine control module programming or electronic calibration.

However, stored fault codes may need to be diagnosed or cleared after the underlying ventilation problem has been repaired.

The exact replacement procedure may vary depending on the BMW chassis, engine variant, and ventilation system configuration. Consult the appropriate BMW repair documentation for vehicle-specific instructions.

Compatibility Notes

• Confirm Your BMW Engine Code: Verify that your vehicle is equipped with the corresponding M43, M43TU, M44, or applicable M42 engine before ordering.

• Verify Both Original BMW Part Numbers: Confirm that your vehicle uses crankcase ventilation valve 11157501567 and breather hose 11151743386. These are separate components and must be matched individually to the vehicle.

• PCV Valve vs. Breather Hose: The PCV valve regulates crankcase ventilation flow, while the breather hose provides the associated gas passage. The components are not interchangeable.

• Confirm Included Components: The original product title describes a crankcase breather hose with a PCV vent valve. Verify that the product package includes both components before purchasing.

• BMW E36 Compatibility: Select E36 316i, 318i, 318is, and 318ti models use the corresponding crankcase ventilation components. However, engine variants and production dates can affect compatibility.

• BMW E46 Compatibility: Early E46 316i and 318i models equipped with M43TU engines are associated with these ventilation components. Later N42/N46-powered models use different configurations.

• BMW Z3 Compatibility: Select Z3 1.8 and 1.9 models equipped with M43 and M44 engines use corresponding crankcase ventilation components. Verify the original hose and valve arrangement before ordering.

• M42 Engine Applications: BMW parts listings also identify PCV valve 11157501567 for select M42 applications. However, the complete hose-and-valve combination should not be assumed compatible without checking both original part numbers.

• M43 vs. M44 Engine Differences: Although both engines use crankcase ventilation systems, their hose routing, mounting configurations, and intake connections can differ.

• Check Historical Part Number Supersessions: Earlier BMW breather hose part numbers may have replacement restrictions. Confirm that the newer hose is compatible with the vehicle's production date and original configuration.

• Inspect the Original Breather Hose: Compare the replacement hose's length, diameter, shape, connection points, and routing with the existing component before installation.

• Check the PCV Valve Sealing Surfaces: Damaged O-rings, deteriorated gaskets, or improperly seated connections can cause vacuum leaks even when the replacement valve is functioning correctly.

• Vacuum Leaks Can Cause Similar Symptoms: Rough idling, unstable engine speed, and lean-running conditions can also result from damaged intake boots, intake manifold gaskets, vacuum lines, or other unmetered-air leaks.

• PCV Valve Failure May Cause Whistling Noises: A damaged internal diaphragm or pressure-regulating component can produce abnormal whistling or hissing noises. However, similar sounds can originate from other intake leaks.

• Excessive Oil Consumption Requires Diagnosis: Increased oil consumption may result from crankcase ventilation problems, but it can also be associated with worn piston rings, valve stem seals, external oil leaks, or other engine-related conditions.

• Inspect Engine Seals and Gaskets: Excessive crankcase pressure can contribute to oil leakage around aging engine seals and gaskets. Replacing the PCV valve may correct the pressure problem, but already damaged seals may require separate repair.

• Check for Excessive Engine Blow-By: Abnormal crankcase pressure can result from restricted ventilation or excessive combustion gases escaping past worn piston rings. Replacing the PCV valve will not correct mechanical engine wear.

• Inspect Related Ventilation Connections: When replacing the breather hose and PCV valve, inspect adjacent hoses, connectors, and intake fittings for similar aging-related deterioration.

• Check for Oil Contamination: Accumulated oil residue inside ventilation hoses can be associated with normal crankcase vapors, but excessive deposits may indicate a ventilation restriction or another engine-related problem.

• Confirm Included Seals and Hardware: Replacement assemblies may be supplied without additional O-rings, gaskets, retaining clips, or mounting hardware. Verify the actual package contents before ordering.

• OEM Reference vs. Genuine BMW: The supplied BMW part numbers identify original equipment components. They do not independently establish that the replacement parts are manufactured or packaged by BMW.

• Verify Fitment Using Your VIN: For the most accurate compatibility confirmation, check both BMW part numbers against the appropriate BMW electronic parts catalog and compare the replacement components with the originals before purchasing.

Maintaining a properly functioning crankcase ventilation system is particularly important for older BMW E36, E46, and Z3 vehicles, where aging breather hoses, deteriorated PCV valve diaphragms, and damaged ventilation connections can contribute to vacuum leaks, unstable idling, excessive oil consumption, and pressure-related engine problems. Replacing a malfunctioning PCV valve and deteriorated breather hose with correctly matched components helps restore the intended crankcase ventilation pathway, supports stable engine operation, and reduces the likelihood of recurring ventilation-related problems. Inspecting the surrounding intake connections, sealing components, and remaining ventilation hoses during replacement can further improve engine reliability and help preserve the smooth, dependable operation of your BMW four-cylinder engine.