do not press the back button…
Enter your VAT number here and click Verify:
Your details have been verified. VAT number registered to:
,
.
Your order will now be zero rated for VAT purposes. We reserve the right to verify these details after your order request has been made and reinstate VAT if required.
Your VAT details were not recognised or were invalid. Your VAT number must be matched to your Billing Country as specified above. This is currently specified as . You do not need to enter the country code part of your VAT number as this has already been selected in your billing address details above.
The VAT number checking service is currently offline. Please supply your VAT details within the comments or special instructions field below and we will apply a VAT discount after placing your order request.
Speed / Reference / Knock Sensors
By OE Match
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
also known are Engine Crankshaft Position Sensor
The engine crankshaft position sensor (CPS) is a critical component that monitors the crankshaft’s position and rotational speed. It sends this data to the engine control unit (ECU), allowing precise control of fuel injection, ignition timing, and other key engine functions. Without accurate input from the CPS, the ECU cannot properly synchronize spark or fuel delivery—leading to poor performance or even a no-start condition.
Crankshaft sensors typically use magnetic or Hall-effect technology:
Magnetic sensors generate a signal with a coil and magnet as the crankshaft rotates.
Hall-effect sensors detect changes in the magnetic field using a semiconductor for highly accurate readings.
Depending on the engine design, the CPS is usually located near the crankshaft pulley, harmonic balancer, flywheel, or transmission. It reads notches or teeth on a tone wheel to create a signal the ECU can interpret.
Over time, heat, vibration, and contaminants (oil, dirt, or metal shavings) can cause the sensor to fail. When this happens, common symptoms include engine stalling, rough idling, misfires, or a no-start condition.
Fits:- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
Common Symptoms of a Failing Crankshaft Position Sensor
· No Start Condition – If the ECU doesn’t receive a proper signal, the engine won’t start.
· Stalling When Warm – The sensor may fail when the engine reaches operating temperature, causing unexpected stalling.
· Erratic or Dead Tachometer – In some vehicles, a faulty CPS can cause the tachometer to behave irregularly.
· Check Engine Code P0335 – A failed internal circuit may trigger this code, though not always.
· Poor Performance at Certain RPMs – Timing issues can cause hesitation, especially at idle or higher RPMs.
· Multiple Cylinder Misfires – Unlike a single bad coil or injector, CPS failure can cause misfires across all cylinders.
This crankshaft sensor is designed for Porsche 911 G models produced between 1984 and 1989. It serves as a pulse generator, transmitting engine speed data to the DME, and is a frequent culprit when the engine experiences irregular performance.
Identified by the Bosch number ending in 005, this sensor was installed in pairs within the vehicle. A reliable and precise pulse generator is crucial for optimal engine electronics performance.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91160621502
The product you are viewing cross references to these numbers
This kit is comprised of the following items:
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 924S 2.5L 1986-87
- Porsche 924S 2.5L 1988
- Porsche 944 2.5L 8V 1982-87
- Porsche 944 2.7L 8V 1988-89
- Porsche 944S 2.5L 16V 1987-88
- Porsche 944S2 3.0L 16V 1989-91
- Porsche 944 Turbo 2.5L 8V 1985-88
- Porsche 944 Turbo 2.5L 8V 1989-91
- Porsche 944 Turbo S 2.5L 8V 1988
Sensor for upper dead centre
Fits:
Porsche 911 1984-89
Porsche 924S 1986-88
Porsche 944 1984-91
Click 'Zoom in' for large parts diagram.
Diagram ref no 24
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91160610800
The product you are viewing cross references to these numbers
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
Please note there are 2 per car, Price is Each
Fits:
Porsche 911 1984-1986 3.2L
Porsche 911 1987-1989 3.2L G50
Porsche 911 1978-1989 3.3L Turbo (930)
The engine crankshaft position sensor (CPS) is a critical component that monitors the crankshaft’s position and rotational speed. It sends this data to the engine control unit (ECU), allowing precise control of fuel injection, ignition timing, and other key engine functions. Without accurate input from the CPS, the ECU cannot properly synchronize spark or fuel delivery—leading to poor performance or even a no-start condition.
Crankshaft sensors typically use magnetic or Hall-effect technology:
Magnetic sensors generate a signal with a coil and magnet as the crankshaft rotates. Hall-effect sensors detect changes in the magnetic field using a semiconductor for highly accurate readings.
Depending on the engine design, the CPS is usually located near the crankshaft pulley, harmonic balancer, flywheel, or transmission. It reads notches or teeth on a tone wheel to create a signal the ECU can interpret.
Over time, heat, vibration, and contaminants (oil, dirt, or metal shavings) can cause the sensor to fail. When this happens, common symptoms include engine stalling, rough idling, misfires, or a no-start condition.
Common Symptoms of a Failing Crankshaft Position Sensor
No Start Condition – If the ECU doesn’t receive a proper signal, the engine won’t start.
Stalling When Warm – The sensor may fail when the engine reaches operating temperature, causing unexpected stalling.
Erratic or Dead Tachometer – In some vehicles, a faulty CPS can cause the tachometer to behave irregularly.
Check Engine Code P0335 – A failed internal circuit may trigger this code, though not always.
Poor Performance at Certain RPMs – Timing issues can cause hesitation, especially at idle or higher RPMs.
Multiple Cylinder Misfires – Unlike a single bad coil or injector, CPS failure can cause misfires across all cylinders.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91160621502
The product you are viewing cross references to these numbers
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 924S 2.5L 1986-87
- Porsche 924S 2.5L 1988
- Porsche 944 2.5L 8V 1982-87
- Porsche 944 2.7L 8V 1988-89
- Porsche 944S 2.5L 16V 1987-88
- Porsche 944S2 3.0L 16V 1989-91
- Porsche 944 Turbo 2.5L 8V 1985-88
- Porsche 944 Turbo 2.5L 8V 1989-91
- Porsche 944 Turbo S 2.5L 8V 1988
- Porsche 968 3.0L 1992-94
- Porsche 968 Sport 3.0L 1994-95
- Porsche 968 CS 3.0L 1993-95
- Porsche 968 Turbo S 3.0L 1993-94
- Porsche 928 4.5L 1978-82
- Porsche 928S 4.7L 1981-83
- Porsche 928S2 4.7L 1984-86
- Porsche 928S4 5.0L 1987-92
- Porsche 928GT 5.0L 1989-91
- Porsche 928GTS 5.4L 1992-95
Fits:
Porsche 928
Porsche 924S
Porsche 944
Porsche 968
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
94460611500
The product you are viewing cross references to these numbers
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
Speed Sensor - G50 Gearbox
Restore accurate vehicle speed measurement and reliable
speedometer operation with this OE Match Speed Sensor for Porsche
911 Carrera models equipped with the G50 gearbox from 1987-1989 and 1989 Porsche 911 turbo models.
Fits:
Mounted on the G50 transmission, the speed sensor monitors gearbox output shaft rotation and generates an electronic signal that is used by the vehicle's speedometer and associated control systems. As one of the key components within the vehicle speed monitoring system, a correctly functioning speed sensor is essential for accurate speed indication and proper operation of related electrical systems.
Manufactured to OE specifications, this direct replacement sensor provides dependable performance and factory-correct fitment for maintenance, fault diagnosis and restoration projects.
What Does the G50 Speed Sensor Do?
The speed sensor measures the rotational speed of the gearbox output shaft and converts this information into an electrical signal.
Its primary functions include:
- Monitoring vehicle road speed
- Operating the speedometer
- Providing vehicle speed information
- Supporting odometer functionality
- Assisting vehicle electrical systems
- Delivering accurate speed readings
- Maintaining factory instrumentation performance
Without a functioning speed sensor, the vehicle's speed indication system cannot operate correctly.
Why Do Speed Sensors Fail?
Speed sensors are exposed to heat, vibration, moisture and years of continuous operation.
Common causes of failure include:
- Internal electronic deterioration
- Heat-related ageing
- Wiring damage
- Corrosion of terminals
- Moisture ingress
- Gearbox contamination
- Physical impact damage
- Age-related component failure
As the sensor ages, signal quality can deteriorate, eventually leading to inaccurate readings or complete failure.
Symptoms of a Faulty Speed Sensor
Common warning signs include:
- Inoperative speedometer
- Erratic speedometer readings
- Intermittent speed display
- Odometer malfunction
- Speedometer needle fluctuation
- Electrical fault diagnosis issues
- Loss of vehicle speed signal
- Dashboard instrumentation faults
In many cases, the speedometer may work intermittently before complete sensor failure occurs.
When Should the Speed Sensor Be Replaced?
Replacement is recommended when:
Diagnosing
speedometer faults
Speed
readings become erratic
The
speedometer stops working
Replacing
damaged wiring
Carrying
out gearbox repairs
Performing
preventative maintenance
Restoring
a Porsche 911 or 911 turbo
Electrical
testing confirms sensor failure
Many Porsche specialists replace ageing sensors when undertaking transmission refurbishment work.
Why Replacement Matters
A functioning speed sensor is important for both safety and vehicle usability.
Benefits of replacement include:
- Accurate speedometer readings
- Reliable odometer operation
- Improved electrical system functionality
- Elimination of intermittent faults
- Enhanced driving confidence
- Reliable vehicle speed monitoring
- Improved restoration quality
- Factory-correct performance
For classic G50-equipped Porsche models, maintaining reliable instrumentation is an important part of preserving the driving experience.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91160691001
The product you are viewing cross references to these numbers
OEMatch Speed / Reference / Knock Sensors — Fit, Function, Confidence
Carefully selected for Porsche models, these sensors provide the signal inputs the engine control system needs to manage ignition, fuelling and detonation control. The following information explains the different types, common failure modes and what to consider when replacing them on Porsche vehicles.
Available Types
- Speed sensors (wheel and crank speed)
- Reference sensors (crankshaft and camshaft position)
- Knock sensors (detonation monitoring)
Understanding OEMatch Speed / Reference / Knock Sensors
OEM (Original Equipment Manufacturer) parts are made by the same company that produced your Porsche’s original speed / reference / knock sensors. OE (Original Equipment) refers to parts matching original specifications for the speed / reference / knock sensors and may be supplied by alternative manufacturers. Aftermarket parts offer alternative options, sometimes with enhanced features or better value. OEMatch supplies non-OEM speed / reference / knock sensors engineered as direct-fit alternatives to OEM parts, made to original-spec dimensions and tolerances for Porsche models. Speed sensors report rotational speed for engine or transmission management; reference sensors provide crank or cam position data used to time injection and ignition; knock sensors detect detonation so the ECU can retard timing to protect the engine.
Benefits Include
- Consistent timing and ignition control to support smooth running
- Improved responsiveness through accurate signal input
- Reduced risk of detonation-related damage when a knock sensor is functioning correctly
Why Speed / Reference / Knock Sensors Wear and Fail
- Thermal stress from proximity to exhaust and hot engine components
- Electrical faults caused by connector corrosion, wiring damage or moisture ingress
- Mechanical damage or contamination to sensing elements from oil, debris or impact
The Importance of Replacing with OEMatch Speed / Reference / Knock Sensors
Replacing worn or damaged sensors restores accurate data flow to the ECU, which helps maintain correct ignition timing, fuelling and detonation control on Porsche engines. Timely replacement can prevent drivability issues such as rough idle, misfire or loss of power and supports consistent fuel economy and emissions behaviour across model ranges.
Advantages
- Direct-fit replacements engineered to match original dimensions and tolerances
- Signal characteristics matched to factory expectations for consistent ECU behaviour
- Robust connector and sealing details to resist heat and contamination
Support & Advice
These items affect safety-critical systems. Installation should be carried out by a qualified technician following model-specific procedures and torque settings. Use calibrated tools and new fasteners where specified.
