Engine Sensors & Switches
About Engine Sensors & Switches
Engine sensors and switches tell the ECU or the dash what is going on: how far the throttle is open, where the crankshaft is, what the oil pressure is and how hot the engine is. When one fails, a bike can crank but not start, stall, run rough, or light a warning lamp.
Pin down the failed part before you buy. Read stored fault codes with a scan tool or the bike's own diagnostic mode, and test the sensor or wiring as the service manual describes. The listings here include throttle position sensors, crank position sensors, engine temperature sensors, oil pressure switches and a throttle sensor pigtail harness for damaged connectors. Applications shown include Harley-Davidson M8 Softail and Touring, Dyna, Polaris and Can-Am, and connectors differ by model and year, so match both. Some throttle position sensors need adjusting or calibrating after they are fitted, which the manual explains.
Brands include Drag Specialties, Parts Unlimited, S&S Cycle, Standard Motor Products and Moose Offroad. Pick your machine in the Ride Finder at the top of the page. Brackets and fasteners are in Brackets & Hardware, and the wider group is Engines & Engine Parts.
FAQs on engine sensors and switches
How can I tell which sensor has failed?
Read the fault codes stored by the ECU, then test the sensor and its wiring as the service manual describes. Replacing parts by guesswork is slow and costly, since the same symptom can come from a connector or a wire.
What does a crank position sensor do?
A crank position sensor tells the ECU where the crankshaft is and how fast it is turning, so it can time the spark and fuel injection. If it fails, the engine may not start or may stall, depending on the model.
Does a throttle position sensor need adjusting after installation?
On some models it does. Some sensors are set in slotted holes and need adjusting, and others need a reset or calibration with a scan tool after installation. Follow the service manual for your bike, since the procedure is model-specific.
Can I clean a sensor instead of replacing it?
First check and clean the connector and inspect the wiring, which often cause the fault. Do not spray cleaners into a sensor itself, and replace it if tests against the service manual figures show it is out of range.
Is an oil pressure switch the same as an oil pressure sender?
No. A switch turns the warning lamp on or off at a set pressure, while a sender gives a changing signal to a gauge. Choose the type your bike uses. Never ride with the oil lamp on.
