Limp mode on a manual

20640 Views 60 Replies 11 Participants Last post by WillysGal, Aug 11, 2014

Black_and_Tan

Discussion Starter · Jun 23, 2014

I was driving on an easy trail earlier today, but hit a bump or rut with some force. The jeep made a jeep, the ESC Malfunction and MIL Lights illuminated, and limp mode was enabled, or what I believe to be limp mode: power drops off in all gears at 3k.

I am going to the dealer tomorrow; just happened to have an appointment.

Any thoughts on what is going on.

My limited searching resulted in auto transmission limps.

I doubt there is any causal relationship, but:

1) Earlier today I pulled out a stuck F150. Low 1st easy pull, no jerking or other "violence."

2) Saturday I got stuck in sand down to the frame, and needed to be pulled out with a winch.

1 - 20 of 61 Posts

GreenMachine13

· #2 · Jun 23, 2014

Sorry, I don't have any answers but I'm interested in what the responses will be. Also, if it's not much trouble, will you report back what the dealer says?

flyinion

· #3 · Jun 23, 2014

Black_and_Tan said:
I was driving on an easy trail earlier today, but hit a bump or rut with some force. The jeep made a jeep, the ESC Malfunction and MIL Lights illuminated, and limp mode was enabled, or what I believe to be limp mode: power drops off in all gears at 3k.

I am going to the dealer tomorrow; just happened to have an appointment.

Any thoughts on what is going on.

My limited searching resulted in auto transmission limps.

I doubt there is any causal relationship, but:

1) Earlier today I pulled out a stuck F150. Low 1st easy pull, no jerking or other "violence."

2) Saturday I got stuck in sand down to the frame, and needed to be pulled out with a winch.

Closest I've had to that is just the ESC light coming on. I had forgotten to turn off traction control (I always do that when off road) that one time. A little while after I turned it off and continued the trail our group was on, the ESC light went away after I assume the Jeep decided things were ok now. It had never done that before or since so I assume I just freaked out the traction control system and it decided to throw a fit for a while. I didn't have the MIL come on though so that's weird. Interested as well to know what the problem is in the end.

daggo66

· #4 · Jun 23, 2014

You damaged a wheel sensor.

R1nZX

· #5 · Jun 23, 2014

I think limp mode is only for automatics. If your power is dropping off at 3k my guess is something else happened.

A wheel sensor, as the previous poster mentioned, would cause your MIL and ESC lights to come on but shouldn't cause the engine computer to reduce power. Did you possibly dent a muffler or exhaust pipe, causing a restriction that reduces power at higher engine speeds? Best theory I can come up with...

Keep us posted.

Black_and_Tan

Discussion Starter · #6 · Jun 23, 2014

GreenMachine13 said:
Sorry, I don't have any answers but I'm interested in what the responses will be. Also, if it's not much trouble, will you report back what the dealer says?

Shall do.

flyinion said:
Closest I've had to that is just the ESC light coming on. I had forgotten to turn off traction control (I always do that when off road) that one time. A little while after I turned it off and continued the trail our group was on, the ESC light went away after I assume the Jeep decided things were ok now. It had never done that before or since so I assume I just freaked out the traction control system and it decided to throw a fit for a while. I didn't have the MIL come on though so that's weird. Interested as well to know what the problem is in the end.

Shall do.

daggo66 said:
You damaged a wheel sensor.

This makes sense as I also heard an unusual noise from my front left wheel.

I read R1's post, but am interested in your opinion: would this problem cause the power drop too?

R1nZX said:
I think limp mode is only for automatics. If your power is dropping off at 3k my guess is something else happened.

A wheel sensor, as the previous poster mentioned, would cause your MIL and ESC lights to come on but shouldn't cause the engine computer to reduce power. Did you possibly dent a muffler or exhaust pipe, causing a restriction that reduces power at higher engine speeds? Best theory I can come up with...

Keep us posted.

Muffler and exhaust look okay.

The power drop off is not a sputter, it is just that: power stops building. I think it is programmed as it does not stall.

Otherwise, shall do.

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Green Mountain Boy

· #7 · Jun 23, 2014

Did you try the key dancing thing to look at what code the MIL threw?

Black_and_Tan

Discussion Starter · #8 · Jun 24, 2014

Green Mountain Boy said:
Did you try the key dancing thing to look at what code the MIL threw?

Tried the sequence twice; nada.

Green Mountain Boy

· #9 · Jun 24, 2014

Whelp that was all I got. Interested like the rest to learn from your experience.

Black_and_Tan

Discussion Starter · #10 · Jun 25, 2014

Update: Dealer diagnosed the problem as a bad cam position sensor. The dealer further explained that the ESC and 3K cut-off were a result of a limp-mode caused by the bad cam position sensor.

A new cam position sensor was installed under warranty.

Wheel sensors checked out ok.

I will post further updates if the problem is not resolved.

GreenMachine13

· #11 · Jun 25, 2014

Black_and_Tan said:
Update: Dealer diagnosed the problem as a bad cam position sensor. The dealer further explained that the ESC and 3K cut-off were a result of a limp-mode caused by the bad cam position sensor. A new cam position sensor was installed under warranty. Wheel sensors checked out ok. I will post further updates if the problem is not resolved.

Interesting. Thanks for reporting back.

Black_and_Tan

Discussion Starter · #12 · Jul 12, 2014

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.

Bent jeep

· #13 · Jul 12, 2014

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.

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.

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Black_and_Tan

Discussion Starter · #14 · Jul 12, 2014

Bent jeep said:
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.

This sounds like a computer problem to me.

Thanks. I'll try that and report back.

Also, forgot to post the code. It is: P0369

Bent jeep

· #15 · Jul 12, 2014

Black_and_Tan said:
Thanks. I'll try that and report back.

Also, forgot to post the code. It is: P0369

P036x are cam sensors sir.

I think 0369 is sensor 2. I'm betting it's a loose ground. Check the grounds on all the cam sensors.

Which one specifically was it last time?

Black_and_Tan

Discussion Starter · #16 · Jul 12, 2014

Bent jeep said:
P036x are cam sensors sir.

I think 0369 is sensor 2. I'm betting it's a loose ground. Check the grounds on all the cam sensors.

Which one specifically was it last time?

My paper work indicates replacement of the right side cam position sensor.

How do I check ground on the sensor?

Black_and_Tan

Discussion Starter · #17 · Jul 12, 2014

Bent jeep said:
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.

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.

Bent jeep

· #18 · Jul 12, 2014

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.

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.

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Black_and_Tan

Discussion Starter · #19 · Jul 12, 2014

Bent jeep said:
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.

First, thank you so much for taking the time and effort to write this up.

I will do as you suggest - particularly the tightening of the battery terminals - and report back.

Bent jeep

· #20 · Jul 12, 2014

Black_and_Tan said:
First, thank you so much for taking the time and effort to write this up.

I will do as you suggest - particularly the tightening of the battery terminals - and report back.

No problem sir!
A loose batt terminal can cause ALL sorts of bizzare problems in any vehicle. I'm willing to bet that is the issue, as typically the simplest solution is usually the right one. But there very well could be a faulty plug, a loose ground, or a million other manufacturing defects that could have happened during assembly.

I would def, still have it given the once over by a service shop and tell them the details of the problem, how you resolved it, and why you feel it is electrical in nature. Then hopefully someone more familiar with the wiring of the engine can ensure that everything is buttoned up properly, since it is under warranty.

Good luck. Let us know how it turns out.

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