involuntary acceleration

[CanoeCG]

2023 Jeep Wrangler 4-Door, 3.6 Automatic: Twice now, as I was coasting at about 10 MPH level driving through a campground, I experienced an involuntary acceleration as though the pedal was being intentionally pushed. It was as though some automatic control was taking over. I gained control by pushing on the brake to slow the engine down to an idle. I came to a stop and just noted that 'that was weird'. It happened twice now. I took the vehicle to the dealer for having someone look at it. Of course, nothing was wrong and there were no error codes to reference. The technician told me that the "transmission control module" was reset. What? Okay, I am to go at it again and see if this happens again. Has anyone experienced this kind of issue? Is there any other thing I should be looking for related to involuntary acceleration? This can't be normal.

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[mwilk012]

Not only is it not normal, it’s damn near impossible unless something is actually hitting the pedal.

 

[CanoeCG]

Okay, on this idea... If while I was trying to maintain the steady slow speed of 8 to 10 MPH, with an ever so slight pressing of the pedal, can there be a miss reading of the pedal position? The transmission downshift, engine revues and the car accelerate.

I compare my experience having a 2017 JK 3.6 engine, automatic, my previous Jeep. I never had this problem. Is there a sensitivity wrong on the pedal position that may be at play? Can the processor reading the pedal position have wrong information? I will continue to test this. Any ideas?

 

[bjm00se]

Is the engine cold? The ECU sometimes keeps the idle RPMs up above 1500 while it's warming up.

Try looking up "High Idle" or "Fast Idle" and see if that seems to describe what you're experiencing.

 

[CanoeCG]

Yes. I missed this element, maybe an important one. Both times this happened, the engine was cold.

 

[azwjowner]

Yes. I missed this element, maybe an important one. Both times this happened, the engine was cold.

For emissions reasons the engine runs 1500 RPM when cold for a few minutes. As a manual owner, it drives me crazy because it makes a cold shift jerky as I can't let off the power. If you're creeping around, it's definitely noticeable.

Next time, sit and let the Jeep idle until the RPMs drop from 1500 down to 750 or so. Then drive. Should be fixed...

 

[mwilk012]

Is the engine cold? The ECU sometimes keeps the idle RPMs up above 1500 while it's warming up.

Try looking up "High Idle" or "Fast Idle" and see if that seems to describe what you're experiencing.

This is disabled when in drive.

 

[jc1003]

Haunted Wrangler!!!

 

[Heimkehr]

Is there any other thing I should be looking for related to involuntary acceleration?

I'd guess the answer is No, but have you installed an aftermarket throttle controller?

 

[Da Capt]

Not only is it not normal, it’s damn near impossible unless something is actually hitting the pedal.

I know it sounds crazy but I’ve had that happen to me once brand new 2017 wrangler. Did some checking in line slot of people had same type of thing happen. It was only once for me never happened again ?‍

 

[azwjowner]

This is disabled when in drive.

It is absolutely not disabled on my manual JL. If it's different for automatics, I don't know. But when I'm moving forward my manual is pulling of its own accord by holding the engine at 1500 RPM.

So I let my Jeep warm up in my garage before departing, thus burning more fuel than if Jeep had left out this feature that was supposed to reduce emissions...

 

[jjvincent]

Yes. I missed this element, maybe an important one. Both times this happened, the engine was cold.

They do have a high idle when cold. Just get a Subaru, those things idle at about 2K when cold.

 

[Pape]

This is disabled when in drive.

Fast idle remain active in all mode when the engine is cold.
I never need to touch the gas in the morning while reversing from my driveway because of the fast idle.

 

[m3reno]

I have a manual Jeep, and when coming to a red light or stop, I leave it in neutral and the Jeep accelerates to 2000 rpm then fluctuates for a few seconds . I'm thinking tps?

 

[TheBirdie72]

“Involuntary Acceleration”

I thought all men had this problem at some point. ?

Don’t feel bad. It’s nothing to be ashamed of. They have folks that specialize in helping you with that.

They are called mechanics, duh.

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