Clunking downshifting after throttle body clean
September 6th, 2019, 9:01 PM
#1
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Clunking downshifting after throttle body clean
I cleaned my throttle body which was really dirty to try and eliminated a rough idle I had.
Afterward around 20miles of driving it definitely upshifted a lot better but I have a terrible downshift really noticeable when slowing from 3rd to 2nd and 2nd to 1st and sounds like transmission is clunking and car is trying to lunge forward.
Figured the computer would re learn after 300-400 miles but still exactly the same! Not sure what to do next. I called a local garage and they said to reset with scan tool to relearn idle and wanted $100 for it? Any ideas?
Afterward around 20miles of driving it definitely upshifted a lot better but I have a terrible downshift really noticeable when slowing from 3rd to 2nd and 2nd to 1st and sounds like transmission is clunking and car is trying to lunge forward.
Figured the computer would re learn after 300-400 miles but still exactly the same! Not sure what to do next. I called a local garage and they said to reset with scan tool to relearn idle and wanted $100 for it? Any ideas?
September 7th, 2019, 2:35 AM
#2
CF Monarch
I cleaned my throttle body which was really dirty to try and eliminated a rough idle I had.
Afterward around 20miles of driving it definitely upshifted a lot better but I have a terrible downshift really noticeable when slowing from 3rd to 2nd and 2nd to 1st and sounds like transmission is clunking and car is trying to lunge forward.
Figured the computer would re learn after 300-400 miles but still exactly the same! Not sure what to do next. I called a local garage and they said to reset with scan tool to relearn idle and wanted $100 for it? Any ideas?
Afterward around 20miles of driving it definitely upshifted a lot better but I have a terrible downshift really noticeable when slowing from 3rd to 2nd and 2nd to 1st and sounds like transmission is clunking and car is trying to lunge forward.
Figured the computer would re learn after 300-400 miles but still exactly the same! Not sure what to do next. I called a local garage and they said to reset with scan tool to relearn idle and wanted $100 for it? Any ideas?
September 10th, 2019, 10:02 AM
#3
Administrator
Its about the drive cycles, you will need to drive , shut off engine, start drive, repeat for about a week and it should settle in. You should be noticing more high idle and not so much shifting issues. If need be, try disconnecting the battery again. Low battery voltage can also affect transmission performance, so consider checking battery voltage and alternator output.
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