I have a problem with my 08 JKU. When I hit a rough spot in the road - bad pavement, railroad tracks, transitions from road to bridge, etc., my engine RPMs will drop and then come back up. If I'm going slow enough, it will sometimes even die. If it's a really rough spot, my check engine light will come on and sometimes also the traction control light.

I have taken it to the dealer twice now. The first time they diagnosed it as the Crank shaft position sensor and replaced it. That seemed to fix the problem until about 5000 miles later and the problem came back. After 3 days in the shop they finally decided to replace the cam shaft position sensor because they couldn't think of anything else (at no charge). That didn't work. This problem seems to have my dealership stumped.

Any ideas?

 

Turn your esp off it will rob power if any traction is lost

 

perhaps something loose or a bad solder joint. At any rate it seems like this will be pretty hard to find until if fails hard.

 

Loose or poor ground?

 

I'm with him it sounds like a loose ground.

 

loose ground to what though?

 

It could be a ground to anything... My jeep wouldn't idol because a random ground on the firewall was lose..

I sat in a parking garage for 2 hours to find a 10mm bolt to be loose

 

Stalling on bumps is often, but not always, attributed to loose or failing electrical connections.

Locate your JK's ecu, and while it's running, smack it with your hand and see if the problem is reproduced (idle speed fluctuation).

I've owned and seen several vehicles with failing ecus die when driving over speed bumps...but you restart and it starts right back up.

 

great idea. where is the ECU? I hope we are on to something here. It makes sense.

 

On your model it should be on the driver's side behind the window washer reservoir. Silver box with connectors going into it.

Just give it a few "slaps" with your hand. Smack it hard enough to simulate a bump....don't go all crazy with a hammer or anything. You're just trying to simulate the jarring of railroad tracks and bumps. Also slap or wiggle the connections into it and follow the cable bundles that leave it, just "lightly" slapping the various connection points.

Also check your battery cables and all their termination points. Wiggle them and look for signs of excessive corrosion.