How to Replace Crank Sensors in a Jeep Cherokee

by Christian Killian

If your Jeep Cherokee stalls unexpectedly, runs rough, starts hard, or doesn't start at all, you may have a bad crankshaft position sensor (CPS). The CPS is responsible for reading the location and speed of the crankshaft and sending that information to the Jeep's central processing unit (CPU), where the information is used to calculate spark timing for the ignition system. If the CPS stops working, the Jeep simply will not run, though a malfunctioning CPS can cause the engine to run rough or start hard. The CPS isn't difficult to change, and if you suspect a defective one, changing it may prevent you from being stranded when it stops working entirely.

Locate the crankshaft position sensor on the driver side of the bell housing, about half way down. It is secured with two 7/16-inch bolts and has a cable that runs up and onto the engine.

Remove the two 7/16-inch bolts from the bracket holding the CPS. A socket with extension or an open end wrench can be used, depending on what works best for you.

Move up the cable about 6 to 8 inches and you will find a clip that holds the cable against the bell housing of the Jeep. Remove the cable from the clip.

Trace the cable from the CPS to the the top of the engine and locate the weather-proof connector where it plugs into the main wiring harness. Unplug the connector, being careful not to break the tab on the connector.

Remove the old CPS and cable from the Jeep. Install the new CPS in the location that you removed the old one from, using the two 7/16-inch bolts. Route the cable from the new CPS up to the clip on the bell housing and install the cable under it.

Route the remaining cable up through the engine compartment and plug in the weather-proof connector. The connector should only go in one way and it should click in when properly seated.

Tip

  • check When routing the new CPS cable, be sure that you do not lay the cable where it could be damaged by moving parts or against the hot manifold.

Warning

  • close When working with any electrical components, it is always important to disconnect your vehicle's battery to avoid the risk of shock or injury.

Items you will need

About the Author

Christian Killian has been a freelance journalist/photojournalist since 2006. After many years of working in auto parts and service positions, Killian decided to move into journalism full-time. He has been published in "1st Responder News" as well as in other trade magazines and newspapers in the last few years.