Limp mode on a manual

Black_and_Tan said:

Earlier today driving on an easy peasy dirt road, and hit a minor - really nothing - bump, and bam: CEL and ESC lights come on, and no power over 3k, again ...

Cannot get to the dealer for another week ...

Frustrating.

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Do u not have a code reader? It could be a million different things.

Have u tried resetting the ECU yet to see if that fixes the issue?



Unplug the negative terminal, turn on your headlights (to bleed the residual power.) leave it sit like that for about 15min while the power bleeds out, then reconnect the terminal and see if the problem goes away.

If it does, just drive it normally for a while to see if it does it again.

This sounds electrical/computer to me. My guess is you are jarring something loose. Make sure the terminals are tight while your under the hood.

Either that or there is a loose ground somewhere feeding the ecu.

Black_and_Tan said:

Did the steps above.

The results:

CEL and ESC lights did not light up, and the Jeep drove normally.

I drove over some local speed bumps at greater speed than the bump I encountered earlier today in an attempt to recreate the problem. Jeep drove normal, despite multiple attempts.

I have a dealership appointment next week, and still plan to bring it in. Not sure if the rest is the fix or not. Something is obviously causing the problem, and with my luck it will happen again on a remote trail, and it will not reset.

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Ok so the right side is cam 2 I believe.

Follow the radiator hose (main hose) to the engine block. Right below it will be the #2 CPS. The sensor will be plugged into a Molex harness. (See image.) make sure the harness is fully seated and follow the wire loom until you see where the ground wire terminates. It's possible it terminates into a common ground, in which it's hard to tell exactly WHERE it could be loose. Your best bet is to tighten all the grounds you can see and ensure they are seated.




This is most def a loose connection somewhere. If the sensor was indeed faulty, then resetting the ecu would initially clear the problem, but as soon as the computer realized the sensor was bad, it would have immediately happened again. Probably minutes after you started driving.

My bet is that something is loose and by jarring the vehicle enough, it shorts and causes the problem.

It is probably:
A: loose battery terminals.
B: loose ground
C: something wrong with the CPS harness plug.

I find it highly improbable that two brand new sensors would be faulty.

It has to be electrical.

I would document as many details as you can with this particular incident in a notebook somewhere so you can tell the dealer exactly what happened and how you cleared it. Hopefully they will figure on it being electrical as well and know exactly how to rectify it. I say write it down, simply because if it was me, I would completely forget in a week.

Edit:
I'm willing to bet it was one of the batt terminals that were loose. If you tightened the guts out of them after you reset the ecu, you may not have the issue ever agin.