How to Replace Knock Sensor 05-10 Chrysler 300
Difficulty: Advanced · About 240 min · Chrysler 300
Replace the knock sensor beneath the intake on a 2005–2010 Chrysler 300, depressurizing the fuel system and removing the intake and fuel rail before restoring all seals, coolant hoses, electrical connections, and fluid levels.
Tools you will need
- Socket Extensions
- Jack Stands
- Brake Parts Cleaner
- Pick
- Gloves
- Flat Blade Screwdriver
- Paper Towels
- Slip-Joint Pliers
- Ratchet
- Wire Brush
- Floor Jack
- Needle nose pliers
- 13mm Wrench
- Complete Metric Socket Set
Parts and supplies
- Knock sensor
- Intake manifold gaskets
- Fuel injector O-rings
- Engine coolant
Steps
Drain coolant and depressurize fuel
Work on a cool engine in a well-ventilated area with no ignition sources. Drain coolant into a pan, then follow the service procedure to relieve fuel pressure; disconnect the battery and keep absorbent material ready for any residual fuel.
Remove the upper intake manifold
Disconnect the throttle body duct, vacuum lines, sensors, and harness retainers, labeling connections as needed. Remove the manifold fasteners and brackets in sequence, then lift the upper manifold clear without damaging its mating surface.
Remove the fuel rail
Cover the open intake ports with clean lint-free material. Disconnect the fuel line using the correct release tool, unplug the injector connectors, and lift the rail evenly so the injectors and seals are not damaged.
Remove the lower manifold
Disconnect the coolant temperature sensor and remaining coolant hoses. Remove the lower manifold fasteners and lift the assembly away, keeping debris out of the exposed engine ports.
Replace the knock sensor
Remove the sensor fastener and unplug the connector. Clean the mounting area without scratching it, install the correct replacement sensor, and tighten its fastener to the vehicle specification.
Reinstall the lower manifold and fuel rail
Clean the gasket surfaces and install new manifold seals in their proper orientation. Remove the port covers, lower the manifold evenly, then reinstall the fuel rail with clean, lubricated injector seals and reconnect the fuel line and wiring.
Reinstall the upper manifold
Fit a new upper manifold gasket and place the manifold without shifting it. Reconnect all hoses, brackets, sensors, and harnesses, tightening fasteners in the specified sequence and to the vehicle torque values.
Restore fluids and check for leaks
Reinstall the fuel pump relay and battery connection, then prime the fuel system using the service procedure and inspect fuel fittings before starting. Refill and bleed coolant according to the manufacturer instructions, warm the engine while monitoring temperature, and recheck for leaks after it cools.
Check your vehicle’s repair manual for exact specifications and fit.