Sensors

Crankshaft and camshaft position sensors are the eyes of your engine's ignition and fuel management systems - they feed real-time position and timing data to the ECU, which uses it to precisely control spark delivery and fuel injection. When they fail, the engine loses that reference signal and performance deteriorates fast. With over 3,500 parts here covering crankshaft position sensors, camshaft position sensors, diesel glow plug controllers, and all associated hardware like O-rings, seals, and magnets, you'll find direct-fit replacements for virtually any make and model. These sensors don't follow a fixed replacement schedule - they're replaced on failure or when diagnostic codes point to them. When buying, prioritize sensors that match your OEM connector type and reluctor wheel tooth count. Aftermarket units from Standard Motor Products, Delphi, or Bosch are solid choices; cheap no-name sensors are a common source of repeat failures and erratic codes.

Signs you need replacement

• Check Engine light with codes P0335–P0338 or P0340–P0349 - these code ranges point directly to crankshaft or camshaft position sensor circuit faults and are the most reliable indicator that a sensor has failed or is failing.
• Engine cranks but won't start - a fully failed crankshaft position sensor gives the ECU no signal to trigger spark or injection, leaving the engine turning over with no ignition event at all.
• Rough idle, misfires, or hesitation under acceleration - an intermittently failing sensor produces a noisy or erratic signal, causing the ECU to mistrigger spark timing and resulting in stumbling or random cylinder misfires.
• Engine stalls at operating temperature and restarts after cooling down - heat-related sensor failure is a classic pattern, particularly on older GM and Ford applications, where the sensor's internal windings expand and short when hot.
• Variable valve timing feels sluggish or VVT-related codes are stored - the camshaft position sensor feeds directly into VVT and VANOS systems; a degraded signal throws off cam phasing and kills the fuel economy and power those systems are designed to deliver.
• Diesel hard-start in cold weather alongside glow plug codes - on diesel applications, a faulty glow plug controller may fail to energize the glow plugs long enough, making cold cranking difficult and storing controller-related DTCs.

Frequently asked questions

• Do crankshaft and camshaft position sensors have a recommended replacement interval? No - these sensors are typically replaced on failure rather than on a mileage schedule. That said, high-mileage vehicles (100,000+ miles) with heat exposure and oil contamination are more prone to failure. If you're doing a timing chain or belt service, it's smart to replace them while access is easy.
• Is OEM worth it, or is aftermarket reliable for position sensors? Quality aftermarket brands - Standard Motor Products (SMP/Blue Streak), Delphi, Bosch, and Denso - meet or exceed OEM specs and are well-proven in the field. Avoid ultra-cheap unbranded sensors; they're a frequent source of repeat no-start and misfire comebacks within months of installation.
• What should I replace at the same time as a position sensor? Check and replace the sensor's O-ring or seal if it's included separately - oil leaks past a worn seal can destroy the new sensor quickly. Also inspect the wiring harness and connector for heat damage or corrosion, both of which cause the same fault codes and are commonly misdiagnosed as sensor failure.