Dodge Repair/'14 Grand Caravan: Throttle out of control
QUESTION: I have a 2014 Dodge Grand Caravan SE with a problem I hope you can help with. When car is moved from park to drive, it takes off by itself with no touch to the accelerator. It will continue for long distance at 5 to 10 MPH. Touch the brake and it stops, but as soon as foot comes off the brake it takes off by itself. It will even continue up a slight incline without me ever touching accelerator.
The dealer service says idle is in spec, and cannot be adjusted (RPM at idle is 600-750, not racing). Suggests warming the car before driving, which is not applicable because this happens whenever putting in gear or foot comes off the brake, not just at first startup. Also says "this engine has a higher idle speed than alternatives." Brakes are fine, but when braking approaching an intersection, stoplight, or turn, must use constant pressure because when you let up on the brake it accelerates instead of coasting.
3.6 -liter V6 24-valve VVT engine
ANSWER: Hi Henry,
The engine's throttle is controlled electrically rather than by a mechanical connection of it to the gas pedal. The gas pedal is an electrical unit which is connected by wires to the engine's throttle body.
There is a procedure described in the '10 service manual, which is the latest I have, which says that the dealer should use their Diagnostic Readout Box in order for the "electronically controlled throttle" unit to "relearn" the electrical characteristics of the pedal whenever the pedal is replaced. I would believe that if the dealer will use their diagnostic readout box and ask the engine computer to "relearn" the characteristic of the electronic throttle control and pedal that the problem will be solved.
So show them this message and ask them to do it, and if that doesn't work then there must be more instruction in a diagnostic trouble code related to the ETC unit which they can find and follow. They may have to replace the throttle pedal.
Fortunately this is under warranty...and they should repair this situation for your safety.
Please read the PS (below) and respond to it.
Thanks for doing that.
---------- FOLLOW-UP ----------
QUESTION: Since I asked the question, the mileage is 15,000, with the major portion on interstates cross country.
I have noticed that the car exhibits a pulsing behavior: at speeds over 40, the car will feel as if the road is undulating, as if someone was tapping the accelerator lightly at one second intervals this can go on for a mile or more, then the car returns to more stable riding.
What is going on?
This sounds like this is another aspect of the problem with the 'electronically controlled throttle' which I suggested to you was the cause of the high idle situation. If the dealer will not try again to service these problems then I would ask for the name of the Chrysler regional service representative and ask the he look into this situation which is clearly a malfunction covered under warranty and also is a safety issue. The electrical throttle positioner is clearly being told to move in ways which appear to be out-of-control.
Thanks for your earlier rating and nomination of me. Feel free to do both again if my answer is helpful to you.