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2012 GLS brake light and ?fuel? issues

  #1  
Old 04-14-2019, 02:17 PM
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Default 2012 GLS brake light and ?fuel? issues

no idea of these are related at all, would seem odd if they were but this day and age, everything is so interrelated

first issue: the three brake lights are coming on entirely on their own with the car parked and off, no keys in the ignition, no one inside. like it has a ghost. pump the brake pedal and they go off.

second issue: when driving, idling along fine at speed, press the accelerator a bit to maintain speed and the rpm's will drop immediately, like the car is dying, rpm's will then randomly rev and die back and forth like its not getting fuel or air or something. if i floor the accelerator at first nothing happens, no reaction whatsoever, then it will rev like mad, like a huge lag in response. the acceleration, deceleration, just goes back and forth with no pattern until i get to a spot where i can just idle along on a flat area at speed and it settles down again. but then again, just even the slightest tap on the accelerator and, whoom, acts like its dying and we do the whole dance of back and forth rpm crap. its far worse going uphill, having to push the accelerator to climb, it wants to die, then surge, then die, then surge, all over the map.

we just had the oil changed and alignment done at a firestone shop the day of the second issue arising and the day before we noticed the first issue

will be calling the only two dealers we have on island tomorrow morning (monday) but this feels totally unreliable, undriveable at this point until this gets diagnosed and solved so any help would be greatly appreciated!!
 
  #2  
Old 04-14-2019, 02:37 PM
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Did the check engine or wrench light ever come on?
If either did, they should have left a code in the computer's memory and they could help provide some direction.
If no codes, sometimes one of the modules in the vehicle's network could be acting up . I can't think of any reason that the 2 could be related except , power reduction possibly due to poor electrical connection(s) , somewhere . Not sure if your vehicle has electronic throttle body control which can mimic those symptoms. Push button start, yes- no ?
 
  #3  
Old 04-14-2019, 04:15 PM
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Originally Posted by hanky View Post
Did the check engine or wrench light ever come on?
If either did, they should have left a code in the computer's memory and they could help provide some direction.
If no codes, sometimes one of the modules in the vehicle's network could be acting up . I can't think of any reason that the 2 could be related except , power reduction possibly due to poor electrical connection(s) , somewhere . Not sure if your vehicle has electronic throttle body control which can mimic those symptoms. Push button start, yes- no ?
thanks so much hanky for the reply!!

no check engine lights. the ESC 'off' light did come on last night, driving in intermittent heavy rains. after stopped and parked for a couple hours, in the drive home it did not come back on.

it's going in to the dealer on May 10 for two recall items to be fixed, an airbag something or other and a software update to the ECU "to protect the engine from excessive connecting rod bearing damage". neither seem related to this either but possibly that's related to one of the modules in the network you're speaking of?

does not have push button start

again, thanks a ton for spit balling this!
 
  #4  
Old 04-14-2019, 04:22 PM
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found this thread that seems like it might be similar to the symptoms we're having.

https://www.cargurus.com/Cars/Discus...33362_ds502885

too many acronyms on modules, sensors, control mechanisms to know confidently if they're fix has anything to do with our issues though
 
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