Misfiring causing sudden downshifting?
07-09-2019, 01:39 PM
#1
Misfiring causing sudden downshifting?
My 2015 3.5 f150 has been experiencing sudden downshifting at random times. Typically, it happens once every hundred miles or so and takes the gears from 5 or 6 all the way to 1 or 2 gear at highway speeds. It is scary especially since we are supposed to be pulling a camper across the west for a few months.
First the dealership said that it was a throttle body issue so I replaced that. Now they are saying that it is spark plugs. Apparently, four out of six misfire at the same time randomly which they said would cause the downshift. However, I just had them replaced with new boots three months ago. The issue did start after a dealer transflush but I do not know if it is a coincidence or not.
First the dealership said that it was a throttle body issue so I replaced that. Now they are saying that it is spark plugs. Apparently, four out of six misfire at the same time randomly which they said would cause the downshift. However, I just had them replaced with new boots three months ago. The issue did start after a dealer transflush but I do not know if it is a coincidence or not.
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kfly (07-09-2019)
07-09-2019, 03:15 PM
#5
The rep just told me that since it only pulled a code for a miss fire, so they want to release it to me and charge me for the diagnostics. However, it has been there three times for the same issues and each time, it is something different.
I asked to check the lead frame and the valve body so we will see. I did read that an improper transflush can cause that damage... but I doubt they would admit it and kind of doubt they are going to even check it.
I asked to check the lead frame and the valve body so we will see. I did read that an improper transflush can cause that damage... but I doubt they would admit it and kind of doubt they are going to even check it.
08-17-2019, 10:01 AM
#6
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My 2015 3.5 f150 has been experiencing sudden downshifting at random times. Typically, it happens once every hundred miles or so and takes the gears from 5 or 6 all the way to 1 or 2 gear at highway speeds. It is scary especially since we are supposed to be pulling a camper across the west for a few months.
First the dealership said that it was a throttle body issue so I replaced that. Now they are saying that it is spark plugs. Apparently, four out of six misfire at the same time randomly which they said would cause the downshift. However, I just had them replaced with new boots three months ago. The issue did start after a dealer transflush but I do not know if it is a coincidence or not. How long we can drive with a misfiring cylinder, visit this link to find more info.
First the dealership said that it was a throttle body issue so I replaced that. Now they are saying that it is spark plugs. Apparently, four out of six misfire at the same time randomly which they said would cause the downshift. However, I just had them replaced with new boots three months ago. The issue did start after a dealer transflush but I do not know if it is a coincidence or not. How long we can drive with a misfiring cylinder, visit this link to find more info.